KR101151565B1 - Electrode for a contact start plasma arc torch and contact start plasma arc torch employing such electrodes - Google Patents

Abstract

The electrode for contact initiating plasma arc torch includes an elongated electrode body formed of an electrically conductive material. The electrode body is movable relative to the torch. An elastic element is used to pass almost all pilot arc currents between the electrode body during a pilot arc operation of a power source, a power connection in electrical communication with the power source, and the plasma arc torch. The electrode and torch may comprise a contact element, the contact element being transferred by having a first surface in electrical communication with the power contact and a second surface in physical contact with and in electrical communication with a corresponding contact surface of the electrode body. Nearly all transferred arc current passes between the power source and the electrode body during arc mode.

Plasma arc torch, pilot arc, contact element, electrode

Description

TECHNICAL FIELD [0001] The present invention relates to an electrode for contact-initiated plasma arc torch and a contact-initiated plasma arc torch employing such electrodes.

The present invention relates to a plasma arc torch, and more particularly, to an electrode and a torch in the field of contact initiated plasma arc torch.

Material processing devices such as plasma arc torches and lasers are widely used for cutting and marking of metal materials known as workpieces. In general, a plasma arc torch includes a torch body, an electrode mounted within the body, a nozzle with a central outlet orifice, electrical connections, passages for cooling and arc control fluids, a vortex ring for controlling fluid flow patterns, and a power source. Include. The gases used in the torch may be non-reactive (eg argon or nitrogen) or reactive (eg oxygen or air). The torch produces a plasma arc, which is a compressed ionized jet of plasma gas with high temperature and high momentum.

One method of producing a plasma arc in a plasma arc torch is the contact initiation method. The contact initiation method includes establishing physical contact and electrical communication between the electrode and the nozzle to create a current path therebetween. The electrode and nozzle may cooperate to create a plasma chamber within the torch body. Current is provided to the electrode and nozzle, and gas is introduced into the plasma chamber. The gas pressure is increased until the pressure is sufficient to separate the electrode and the nozzle. The separation creates an arc between the electrode and the nozzle in the plasma chamber. The arc ionizes the introduced gas to produce a plasma jet, which can be transferred to a workpiece for material processing. In some applications, the power supply is adapted to provide a first current known as a pilot current during generation of the arc and a second current known as the transferred arc current when the plasma jet is transferred to the workpiece.

Various structures can be used to generate the arc. For example, the electrode can move within the torch body away from the fixed nozzle. This structure is called "blow-back" contact initiation because the gas pressure causes the electrode to move away from the workpiece. In another structure, the nozzle can move away from the relatively fixed electrode. This structure is called “blow-forward” contact initiation because the gas pressure moves the nozzle towards the workpiece. In another structure, other torch parts (eg, the vortex) Ring) may be moved between the fixed electrode and the nozzle.

Certain parts of the material processing apparatus are degraded due to repeated use. Such “consumable” parts, in the case of a plasma arc torch, include the electrode, vortex ring, nozzle, and shield. In addition, in the process of initiating the torch using the contact initiation method, various consumable parts may be misaligned, which reduces the lifespan of the parts as well as the accuracy and reproducibility of the plasma jet position. Ideally, these parts are easily replaceable in the field. Nevertheless, replacing consumable parts leads to equipment downtime and reduced productivity.

In a blow-back method of contact initiating a plasma arc torch, the electrode is moved away from the nozzle to start a pilot arc between the electrode and the nozzle. Adjacent ends of the electrodes (eg, located away from the workpiece) engage the power contacts that form part of the torch body. Movement of the electrode away from the nozzle also moves the power contact. Repeated use of the torch results in wear of both the power contacts and the electrodes. Replacement of the electrodes is routine for plasma mark torch operation and the process is performed in a conventional manner. However, replacement of a power contact requires dismantling of the torch body, which can be time consuming and expensive since the power contact is not designed as a consumable part. Some blow-back torches involve moving the power contacts relative to a relatively fixed torch body. The movement of the power contacts and the effectiveness of the torch are affected by the strength and stiffness of the power cable connecting the power contacts to the power source.

For example, FIG. 1 is a cross-sectional view of a known contact initiated plasma arc torch. The system 100 includes a power contact (not shown) that is in electrical communication via a current-transfer cable 104 and a power contact 108 that provides current to the torch 112. The torch 112 includes a cathode block 116 that is electrically insulated from and surrounds the power contact 108. The power contact 108 is in contact with the adjacent end 120 of the electrically conductive electrode 124. A spring 128 disposed within the cathode block 116 reacts against the surface 132 of the cathode block 116 to force the power contact 108 and the electrode 124 toward the electrically conductive nozzle 136 do. The electrode 124 is pressed into contact with the nozzle 136 by the spring prior to initiation of an arc for processing a workpiece (not shown).

The current path consists of the cable 104 from the power contact 108, the electrode 124, and the nozzle 136. Current can be passed along the current path. The electrode 124 cooperates with the nozzle 136 to form part of the plasma chamber 140. The plasma gas may be supplied to the plasma chamber 140 to increase the pressure in the plasma chamber 140 to overcome the force provided by the spring 128. The pressure causes the electrode 124 and the power contact 108 to be away from the nozzle 136. The potential difference develops as the gap 144 between them increases between the electrode 124 (eg, the cathode) and the nozzle 136 (eg, the anode). An arc (not shown) is initiated across the gap 144 for workpiece processing by ionizing gas particles.

One disadvantage of the system 100 is that as the electrode 124 moves to initiate an arc, the power contact 108 must also move. As the current carrying capacity of the cable 104 increases, the size of the cable 104 increases, but the flexibility of the cable 104 decreases. The reduced flexibility of the cable 104 reduces the flexibility and maneuverability of the torch 112. In addition, the power contact 108 and the negative block 116 require a relatively tight tolerance (eg, a relatively small gap between the power contact 108 and the negative block 116). The relatively tight tolerance positions and guides the power contact 108 during movement of the power contact 108, for example during the start of a pilot arc.

There is a need for such a torch electrode that optimizes the operation of a contact initiating plasma arc torch without premature failure. There is also a need for a contact initiating torch that employs the concepts herein to maximize component life within current torch designs. It is therefore an object of the present invention to provide long life electrodes and components for use as electrodes in plasma arc torch. Another object of the present invention is to provide a structure that reduces wear to parts of the torch that are not designed to be consumable. It is another object of the present invention to provide alignment characteristics for torch components during torch operation (eg, pilot arc and transferred arc modes).

In one aspect, the electrode for the plasma arc torch has a power connection in electrical communication with the power source. The electrode comprises an elongate electrode body made of an electrically conductive material and defining a longitudinal axis. The electrode includes an elastic element that passes almost all pilot arc currents between the power source and the electrode body during pilot arc operation of the plasma arc torch. The elastic element performs both electrical and mechanical functions, which may be referred to as the dual function element of the torch. The elastic element includes an electrically conductive material to facilitate both the transfer of pilot arc current and dissipation of the heat associated with the pilot arc current so that the elastic element does not melt during initiation of the pilot arc. The conductive material may for example be selected based on the rated current of the conductive material. The elastic element includes a path of minimum resistance and / or highest conductance for transferring pilot current between the power connection and the electrode body. In addition, the mechanical properties of the elastic element facilitate the movement of the electrode body to initiate contact of the plasma arc torch. In some embodiments, the elastic element helps to align the electrode body with respect to the torch.

In some embodiments, the electrode body is longitudinally movable relative to the torch. In some embodiments, the electrode body comprises a reaction surface disposed in a spaced relationship relative to an adjacent end of the electrode body located spaced from the workpiece. The reaction surface is formed to be in electrical communication with an electrically conductive elastic element. In some embodiments, the reaction surface includes radially extending flanges integrally formed with the electrode body.

In some embodiments, the elastic element is fixed relative to the electrode body. For example, the elastic element can be fixed by a diameter interference fit or friction joint. In some embodiments, the elastic element is disposed adjacent the distal end of the electrode body, the distal end including a light emitting element. In some embodiments, the elastic element is integrally formed with the electrode body. In some embodiments, the pilot arc operation includes initiation of a pilot arc. In some embodiments, pilot arc operation includes the start of a pilot arc and the duration of time after the start of the pilot arc before the arc is transported to the workpiece or before the torch is operated in an arced mode.

In some embodiments, the electrode further comprises a hollow body for holding the elastic element and slidably receiving the electrode body.

In another aspect, an electrode for a plasma arc torch is provided. The electrode includes an elongated electrode body made of an electrically conductive material defining a longitudinal axis, and a distal end comprising a light emitting element. The electrode body is movable relative to the torch. The electrode includes a contact element. The contact element includes a first surface that facilitates electrical conduction with a power source and a second surface that facilitates electrical conduction with a corresponding contact surface of the electrode body when the torch is operated in a conveyed arc mode. And said second surface of said contact element is free of contact with said contact surface of said electrode body during initiation of a pilot arc.

The electrode body is movable in the axial direction with respect to the torch. In some embodiments, the second surface is formed to be in physical contact with the contact surface of the electrode body when the torch is operated in the transferred arc mode. In some embodiments, the electrode body includes a reaction surface in contact with a conductive elastic element and disposed in a spaced relationship relative to an adjacent end of the electrode body. The adjacent end is disposed away from the distal end including the light emitting element. The reaction surface may be defined by a radially extending flange formed integrally with the electrode body.

In some embodiments, the electrode comprises an electrically conductive elastic element in electrical communication with at least one of the contact element and the electrode body. The elastic element may be integrally formed with at least one of the electrode body and the contact element. In some embodiments, the elastic element is disposed adjacent the distal end of the electrode body. The elastic element may be held by the electrode body. In some embodiments, the electrode body comprises a reaction surface integrally formed with the electrode body. The elastic element may be disposed between the reaction surface and the second surface of the contact element.

In some embodiments, the resilient element is configured to pass almost all pilot arc current between the power source and the electrode body during pilot arc operation. The elastic element may include at least one of a spring and a wire. In some embodiments, at least a portion of the contact element is slidably coupled with the electrode body. In some embodiments, the portion of the contact element facilitates passage of pilot arc current between the contact element and the electrode body when the contact element is slidably coupled with the electrode body. The contact element may be held by the electrode body. In some embodiments, the contact element comprises a connecting member defining an alignment surface that limits the radial movement of the electrode body. The connection member may be integrally formed with the contact element. In some embodiments, the electrode body includes a receptor disposed adjacent an adjacent end of the electrode body spaced from the workpiece. The receptor is formed to prevent the contact element from being released from the electrode body.

In another aspect, a contact element is provided for passing a current between a power source and a torch electrode slidably mounted in a torch body of a contact initiating plasma arc torch. The contact element includes a first surface that facilitates electrical conduction with the power source and a second surface for electrical conduction with a contact surface defined by an adjacent end of the torch electrode. When the torch electrode is in physical contact with the second surface, at least a portion of the transferred arc current passes through the contact element and passes between the power source and the torch electrode for operation of the torch in the transferred arc mode. The contact element includes an electrically conductive elastic element disposed adjacent to the electrode body for passing almost all pilot arc currents from the power source to the electrode body during pilot arc operation.

In some embodiments, the connecting member extends from the second surface and slidably engages with the electrode body. The connecting member may be integrally formed with the second surface. In some embodiments, the connecting member includes a third surface formed to pass a portion of the transferred arc current between the power source and the electrode body when the torch is operated in the transferred arc mode. In some embodiments, the contact element comprises a receptacle surrounding a portion of an adjacent end of the electrode body. The elastic element may be disposed in the accommodation portion of the contact element. In some embodiments, at least one of the first surface and the second surface defines an annular surface.

In some embodiments, the contact element has a third surface that is in electrical communication with the power source and passes a portion of the transferred arc current between the power source and the electrode body when the torch is operated in the transferred arc mode. Include. In some embodiments, the contact element comprises an alignment defining an axis. The alignment portion is spaced apart from an adjacent end of the electrode body and is formed to limit radial movement of the electrode body.

In another aspect, the invention features an electrode for plasma arc torch. The electrode comprises an elongate electrode body made of an electrically conductive material and defining a longitudinal axis. The electrode body includes a distal end defining a hole for receiving a light emitting element and an adjacent end defining a contact surface in electrical communication with a power source. The electrode body includes a receptor disposed within the adjacent end of the electrode body that is formed to receive at least a portion of the contact element. Wherein the first portion of the contact element is physically spaced from the electrode body during the start of the pilot arc and the first portion of the contact element is between the power source and the electrode body when the torch is operated in the transferred arc mode. To pass almost all of the transferred arc current. The aperture and the receptor are separated by the electrode body.

In some embodiments, at least a portion of the contact surface is disposed within the receptor. The contact element may comprise an annular structure. The receptor includes a cylindrical portion and a confinement surface disposed at an adjacent end of the receptor that reacts to a portion of the contact element to limit release of the contact element from the receptor. The confinement surface may comprise an annular structure.

In some embodiments, the cylindrical portion is defined by a first diameter, the limiting surface comprises a second surface, and the distal region of the connecting member of the contact element defines a third diameter, the third The diameter is larger than the second diameter and smaller than the first diameter. The distal region may be a distal end of the connecting member. In some embodiments, the receptor includes a surface having radial dimensions formed along the axis of the receptor for limiting radial movement of the electrode body. The radially dimensioned surface is for physical contact with a portion of the contact element received by the receptor.

In some embodiments, the electrode body comprises a reaction surface disposed in a spaced relationship relative to the contact surface. The reaction surface may be a radially extending flange integrally formed with the electrode body. In some embodiments, the electrode comprises an electrically conductive elastic element secured by the electrode body. The reaction surface may be in contact with the elastic conductive element. The elastic element can be fixed by a diameter interference fit. The elastic element may be disposed on the receptor.

In another aspect, there is provided a contact element for passing a current between an electrode body and a power supply, which are slidably provided with a torch body of a contact initiating plasma arc torch. The electrode body includes a distal end including a light emitting device. The contact element includes a first surface that facilitates electrical conduction with the power source and a second surface that facilitates electrical conduction with an adjacent end of the electrode body. The second surface contacts the adjacent end during the transferred arc mode without contacting the adjacent end during initiation of a pilot arc, such that at least of the transferred arc current from the power source when the torch is operated in the transferred arc mode. A portion passes between the first and second surfaces of the contact element to reach the electrode body.

In some embodiments, the contact element comprises an electrically conductive carbon element positioned adjacent to the electrode body. The elastic element is for passing almost all pilot arc currents between the power supply and the electrode body during pilot arc initiation. The contact element may include a connection member disposed between the second surface and the electrode body. In some embodiments, the connecting member is integrally formed with the second surface. In some embodiments, the connecting member defines an axial and alignment surface that is spaced apart from the adjacent end to limit radial movement of the electrode body. In some embodiments, the first surface, the second surface, or both define an annular surface.

The contact element may comprise a vortex ring portion. In some embodiments, the contact element is integrally formed with the vortex ring portion. The vortex ring portion exerts radial motion with gas flowing through the plasma arc torch. The vortex ring portion may also insulate the electrode body from the nozzle and direct the gas toward a portion of the electrode body that defines a plurality of fins. The swirl ring portion can also limit radial movement of the electrode body within the torch. In some embodiments, the swirl ring portion can perform both of these functions. In some embodiments, the vortex ring portion performs one or more of these functions. Functions not performed by the vortex ring portion may be performed by one or more individual components.

In another aspect, a plasma arc torch is provided. The plasma arc torch includes a power source for providing current to the torch. The torch includes a plasma chamber defined by a nozzle and an electrically conductive electrode body slidably mounted within the torch along an axis defined by the proximal and distal ends of the electrode body. The proximal end defines a contact surface, the distal end being disposed adjacent the outlet orifice of the nozzle. The torch includes a power contact disposed in a fixed position relative to the plasma chamber. The power contact is in electrical communication with the power source. The torch includes an elastically conductive element that passes almost all pilot arc currents between the power contact and the contact surface of the electrode body during pilot arc operation. The torch includes a contact element. The contact element comprises a first surface in electrical communication with the power contact and a second surface in electrical communication with a corresponding contact surface of the electrode body. The contact element may pass an arc current transferred between the power source and the electrode body during the transferred arc mode.

In some embodiments, the resilient conductive element presses the electrode body towards the nozzle. In some embodiments, the contact element is disposed in a fixed position with respect to the electrode body. The contact element may be integrally formed with the power contact. In some embodiments, the torch includes a shield defining an outlet port located adjacent the outlet orifice of the nozzle. The shield may be mounted on a fixed cap supported on the torch body of the plasma arc torch. In some embodiments, the torch exerts radial motion with respect to the gas flowing through the torch.

In another aspect, a plasma arc torch is provided. The plasma arc torch includes a power source for providing a current to the torch. The torch includes a plasma chamber defined by electrically conductive electrodes and nozzles slidably mounted within the torch along an axis defined by adjacent ends and distal ends of the electrode body. The electrode body defines a contact surface, the distal end being disposed adjacent the outlet orifice of the nozzle. The torch includes a power contact disposed in a fixed position relative to the plasma chamber and is in electrical communication with the power source. The torch includes an elastically conductive element that passes almost all pilot arc currents between the contact surface of the electrode body and the power contact during pilot arc operation of the plasma arc torch. The elastic conductive element presses the electrode body toward the nozzle.

In some embodiments, the power contact includes a first surface that facilitates physical contact and electrical communication with a corresponding second progressive surface of the electrode body when the torch is operated in the transferred arc mode. The first surface of the power contact is characterized in that there is no contact with the corresponding second contact surface of the electrode body during initiation of a pilot arc.

In another aspect, an electrode for a plasma arc torch is provided that is in electrical communication with a power source. The electrode comprises an elongate electrode body made of an electrically conductive material and defining a longitudinal axis. The electrode body includes a first surface in electrical communication with a first conductive element that facilitates passage of pilot arc current between the power source and the electrode body during initiation of a pilot arc. The electrode body also includes a second surface located spaced from the first surface. The second surface may be in physical contact with and in electrical communication with a corresponding surface of a power contact that facilitates passage of almost all transferred arc current between the power source and the electrode body during transferred arc operation. The second surface of the electrode body is characterized in that there is no contact with the corresponding surface of the power contact during the start of the pilot arc.

In some embodiments, the electrode body is longitudinally movable relative to the torch. Although embodiments disclosed herein relate primarily to longitudinal movement of the electrode body within the torch, some embodiments feature an electrode body that is movable in a non-longitudinal direction along an axis. For example, the electrode body may move in a direction transverse to the longitudinal axis during initiation of a pilot arc or other torch operation. The electrode body may also move in rotation about the axis. In some embodiments, the other movement of the electrode body may be a combination of longitudinal, transverse or rotational movement (eg, twist or bend movement).

In another aspect, a plasma torch component is provided that houses an electrode. The component includes an elongate hollow body and an electrically conductive elastic member that facilitates electrical conduction of the pilot arc. The elongate hollow body has a first end and a second end. The elongate hollow body is (a) an inner surface, (b) one or more contours, steps or flanges disposed on the inner surface and disposed between the first and second ends of the hollow body, wherein At least one contour, step, or flange defining an opening of a shape adapted to slidably receive the complementary portion of the electrode is (c) within the first end of the hollow body of a size to receive an electrical contact element. A first opening, and d) a second opening in said second end of said hollow body sized to slidably receive said electrode. The electrically conductive elastic member is disposed in the hollow body such that the elastic member is held at least partially within the hollow body by the one or more contours, steps or flanges, the elastic member being the first opening hole. Is sorted on.

In some embodiments, the hollow body of the part further comprises a plurality of holes adjacent the second opening of the hollow body for applying a vortex flow to the gas. Embodiments also include contact elements disposed within the first end of the hollow body. In this embodiment, the contact element maintains the elastic member in the hollow body and facilitates electrical coupling between the elastic member and the power source.

In another aspect, an electrode for a contact initiating plasma arc torch is provided. The electrode includes an elongated electrode body formed of an electrically conductive material and a second end positioned adjacent to the electrode body. The electrode body defines a longitudinal axis and a distal end for receiving the light emitting element. The second end defines an axial extension having a first length along a first direction and a second length along a second direction. The second length of the axial extension is greater than the first length.

In some embodiments, the first and second directions of the axial extension define a surface orthogonal to the longitudinal axis. In some embodiments, the first and second directions are orthogonal to one another. The electrode may comprise two or more axial extensions, each axial extension having a respective first length and a respective second length greater than the respective first length. In some embodiments, the two or more axial extensions are arranged at equal intervals about the axis. The value of the operating current for the transferred arc actuation of the plasma arc torch can be related to the number of the two or more axial extensions. That is, a specific operating current may correspond to a specific number of axial extensions located on the electrode body.

In some embodiments, the first and second directions of the axial extension extend radially away from the axis. In one embodiment, the first and second directions define a surface comprising a first region and a second region. The first region is in electrical communication with an elastic element that passes almost all pilot arc current therebetween during pilot arc initiation. The second region is moved in electrical contact with the physical contact with the power contact for the transferred arc operation. In some embodiments, the power contacts are in electrical communication with a power source. The power contact includes a first contact surface in physical contact with and electrically in contact with the second region and a second contact surface in electrical communication with the elastic member.

In some embodiments, the second end and the electrode body are integrally formed. In some embodiments, the electrode further comprises a vortex ring that defines an interior surface disposed relative to the shoulder. The shoulder defines a boundary of the complementary contour, facilitating the passage of the second length through the second length when the boundary of the complementary contour is aligned. In some embodiments, the shoulder prevents passage of the axial extension therethrough when the boundary between the second length and the complementary contour is not aligned. The boundary line of the complementary contour may define a third length greater than the second length. In some embodiments, the second length of the axial extension is approximately equal to the width of the electrode body.

In another aspect, a swirl ring for a contact initiated plasma arc torch is provided. The vortex ring is (a) a hollow body formed of an insulating material along a longitudinal axis and defining an outer surface and an inner surface, (b) one or more gas passages extending from the outer surface to the inner surface, and ( c) a shoulder portion disposed relative to the inner surface and defining an open aperture of the contour that can receive the complementary portion of the electrode body.

In some embodiments of this aspect, the shoulder portion allows the complementary portion of the electrode body to pass therethrough when the opening and the complementary portion of the contour are aligned. In some embodiments, the shoulder portion prevents the passage of the complementary portion of the electrode body through the opening and the complementary portion of the contour if it is not aligned. The shoulder portion may include a reaction portion to limit the angular displacement of the electrode body. In one embodiment, the opening of the contour defines an inner diameter and an outer diameter. The vortex ring also includes two or more portions within the opening of the contour that are arranged in a conformal structure about the axis, wherein the two or more portions are defined by the outer diameter of the opening of the contour.

In another aspect, a component for a contact initiated plasma arc torch is provided. The part comprises a hollow body defining the longitudinal axis and the inner surface of the body. The inner surface of the body includes one or more contours, steps, or flanges that define an opening in a shape that can slidably receive a complementary portion of the electrode body along the axis. The opening of the shape has a first length along a first direction and a second length along a second direction. The second length is greater than the first length.

In some embodiments, the component further includes a vortex ring portion defining one or more apertures that penetrate the fluid from the exterior, interior and exterior to the interior. The swirl ring portion may be integrally formed with the hollow body. In some embodiments, the contour, step or flange is in contact with the corresponding surface of the elastic element to prevent the elastic element from separating from the torch.

In another aspect, an electrode for a contact initiating plasma torch is provided. The electrode includes an elongated electrode body and a second end positioned adjacent to the electrode body. The elongated electrode body is formed of an electrically conductive material and defines a distal end for receiving the longitudinal axis and the light emitting element. The second end defines a first surface having a first diameter about the longitudinal axis and one or more regions extending adjacent from the first surface. Each of the one or more regions has a portion that is in physical contact with the elastic conductive element and in electrical communication to facilitate the flow of pilot current.

In some embodiments of this aspect, the first surface of the second end of the electrode is moved in physical contact with and electrically through the corresponding surface of the power contact to facilitate passage of the transferred arc current. In some embodiments, the electrode further comprises a second surface positioned relative to the first surface. The second surface is brought into physical contact with and electrically connected to the corresponding surface of the power contact to facilitate passage of the transferred arc current. In some embodiments, the second surface is located parallel to the first surface and spaced apart relative to the first surface or located adjacent to the first surface.

In some embodiments, one or more regions extending adjacent from the first surface of the second end are substantially parallel to the longitudinal axis. Each of the one or more regions may define a second direction smaller than the first diameter. In some embodiments, each of the one or more regions is equally spaced radially from the longitudinal axis.

In another aspect, an electrode for a contact initiating arc torch is provided. The electrode is formed of an electrically conductive material and includes a second end positioned adjacent to the electrode body, a distal end to receive the light emitting element, and an elongated body defining a longitudinal axis. The second end is slidably coupled along the axis to an inner surface of the component of the plasma arc torch, means for facilitating the flow of pilot current therebetween electrically through the elastic element during pilot arc initiation, and Means for communicating electrically upon movement of the material contact with the power contact during the transferred arc operation.

In another aspect, an electrode for a contact initiating plasma arc torch is provided. The electrode is an elongated electrode body formed of an electrically conductive material and defining an electrode width, the elongated body being slidably attached to an adjacent member, (b) the distal end of the electrode body, (c) the distal end of the electrode body. A light emitting element positioned at, (d) a second end of the electrode body having a surface receiving an operating current, and (e) a radial extension placed at a position between the distal end and the second end of the electrode body. . The radial extension has a surface subjected to pilot arc current. The radial extension has a first portion having a first length and a second portion having a second length. The second length is greater than the electrode width and the first length.

In other embodiments of the invention, any of the foregoing aspects may include one or more of the above features. One embodiment of the present invention may provide all of the above-described features and advantages. These and other features can be more clearly understood with reference to the following description and the accompanying drawings, which are exemplary and are not necessarily to scale.

1 is a cross-sectional view of a known contact initiated plasma arc torch.

2A is an exploded view of an electrode body, a conductive elastic element, and a power contact in an embodiment in accordance with the present invention.

2B is a cross-sectional view of a preferred contact initiating plasma arc torch employing the components of FIG. 2A prior to pilot arc operation.

2C is a cross-sectional view of the plasma arc torch of FIG. 2B during the transferred arc mode.

3A is a cross-sectional view of a preferred embodiment of an electrode used in a contact initiated plasma arc torch.

3B is a detailed view of the components of the electrode of FIG. 3A before assembly of the embodiment of the electrode.

4A is a cross-sectional view of a preferred contact initiating plasma arc torch including example components in a structure prior to pilot arc operation.

4B is a cross sectional view of the plasma arc torch of FIG. 4A including exemplary components in a structure during a transferred arc mode.

5A is a cross-section of a preferred electrode that includes a contact element and an elastic conductive element disposed within the receptor of the electrode body.

5B shows the electrode of FIG. 5A disposed in the transferred arc mode.

6A is a cross-sectional view of a preferred electrode including contact elements and elastic conductive elements disposed at adjacent ends of the electrode body.

6B shows the electrode of FIG. 6A disposed in the transferred arc mode.

7A shows a partial exploded view of a preferred contact element, elastic element, and power contact that embody the principles of the present invention.

FIG. 7B shows the component of FIG. 7A disposed in a plasma arc torch operation. FIG.

8A is a cross-sectional view of another embodiment of an electrode body, an elastic conductive element, and a contact element before installation in a plasma arc torch.

8B shows the structure of the component of FIG. 8A during the transferred arc mode.

9 is a cross-sectional view of another embodiment of an electrode embodying the present invention.

10A is a perspective view of a preferred contact element and an elastic conductive element.

10B is a partial cross-sectional view of the plasma arc torch employing the components of FIG. 10A during pilot arc operation.

11A shows a preferred contact element for use in a contact initiated plasma arc torch.

FIG. 11B shows the contact element of FIG. 11A rotated 90 degrees about a vertical axis. FIG.

12A is a partial cross-sectional perspective view of an assembly for a contact initiating plasma arc torch.

12B is an exploded perspective view of the assembly of FIG. 12A.

12C is a top view of a portion of the assembly of FIG. 12A.

13A is a perspective view of an electrode of a contact initiating plasma arc torch.

13B is a top view of the assembly used for the electrode of FIG. 13A.

14A is a perspective view of an electrode of a contact initiating plasma arc torch.

14B is a top view of the assembly used for the electrode of FIG. 14A.

15A is a perspective view of an electrode of a contact initiating plasma arc torch.

15B is a plan view of the assembly used for the electrode of FIG. 15A.

16 is a perspective view of an electrode of a contact initiating plasma arc torch.

2A is an exploded view of an electrode body, a conductive elastic element, and a power contact in an embodiment in accordance with the present invention. The system 200 includes an electrode body 202, an elastic conductive element 204, and a power contact 206 (also called a power connection). The power contact 206 is in electrical communication with a power source (not shown), for example a power cable (eg, the power cable 104 of FIG. 1). The power supply provides a current to the power contact 206 that is used to operate a plasma arc torch similar to the torch 112 of FIG. 1. The electrode body 202 includes a reaction surface 208 configured to be in electrical communication with the elastic conductive element 204. The reaction surface 208 is disposed in a spaced apart relationship with an adjacent end 210 of the electrode body 202. In some embodiments the reaction surface 208 is integrally formed with the electrode body 202. For example, the reaction surface 208 can be made of the same material as the electrode body 202 or made of a different material, but can also be bonded or secured to the electrode body 202.

The adjacent end 210 of the electrode body 202 is disposed opposite the distal end 212. In the illustrated embodiment, the diameter of the distal end 212 is greater than the diameter of the proximal end 210 so that the elastomeric conductive element 204 surrounds the proximal end 210 when installed in the torch. In other words, the diameter of the adjacent end portion 210 is smaller than the inner diameter of the elastic conductive element 204. In another embodiment, the adjacent end 210 is equal to or larger than the diameter of the distal end 212.

The power contact 206 includes a surface 214 that reacts with the resilient conductive element 204. The resilient conductive element 204 reacts to the relatively fixed surface 214 and the reaction surface 208 of the relatively movable electrode body 202 such that the electrode body is connected to the power contact 206 during pilot arc operation. Press away from. The electrode body 202 defines a contact surface 216 configured to be in physical contact with and in electrical communication with a corresponding surface 218 of the power contact 206. During the second half of the pilot arc operation and during the transferred arc mode, the contact surface 216 comes into contact with the corresponding surface 218. The portion 220 of the power contact 206 adjacent the surface 218 and extending to the surface 214 defines a diameter such that the elastic conductive element 204 surrounds the portion 220. do.

In some embodiments, the power contact 206 may be manufactured as part of the power contact 108 of FIG. 1 (eg, the power contact 108 to include the features of the power contact 206). By processing). These embodiments allow a user to employ the concept described with respect to FIG. 2A in the conventional torch system 112 of FIG. In some embodiments, the power contacts 108 may be grooved in the power contacts 108 and secured to the power contacts 108 with clips or retaining rings (not shown) relative to the torch 112. It may be located in the blow-back position of FIG. In this manner, the power contact 108 remains fixed relative to the torch 112 during pilot arc operation and transferred arc operation. In general, any of the above embodiments may be used in the torch system 112 of FIG. 1 by changing the power contact 108 in accordance with the principles herein.

The relatively fixed power contact 108 requires less flexibility from the power cable. Suitable currents suitable for use as pilot arc currents are between 10 and 31 amps. The current during the transferred arc operation can go up to approximately 200 amps. However, currents of approximately 200 amps or more, such as 400 amps, are also within the scope of the present invention. In some embodiments, the power contact 108 is made of tellurium copper, brass, copper, or other material suitable for passing current during pilot arc operation and transferred arc operation.

In general, pilot arc operation refers to the period between the provision of current to the electrode body 202 and the transfer of the plasma arc to the workpiece. In more detail, pilot arc operation includes the start of a pilot arc and a period of time after the start of the pilot arc, but before the transfer of the arc to the workpiece. Some torch designs include a safety mechanism that terminates pilot arc operation after some time, regardless of whether the plasma arc has been transferred to the workpiece. This mechanism is designed to extend the operating life of the torch component and increase safety by limiting the time (eg, workpiece processing) that the torch is operated without specific application.

In some embodiments, the resilient conductive element 204 is secured to the electrode body 202 or the power contact 206. In another embodiment, the resilient conductive element 204 is secured to the electrode body 202 and the power contact 206. For example, the elastic conductive element 204 may be fixed to the electrode body 202 or the power contact 206 by welding, soldering, gluing, or other fastening. In some embodiments, the resilient conductive element 204 is secured to the adjacent end 208 of the electrode body 202 by a diameter interference fit or other frictional junction. For example, the outer diameter of the adjacent end 208 of the electrode body is slightly larger than the inner diameter of the elastic conductive element 204. In some embodiments, the adjacent end 208 of the electrode body 202 is characterized by an extension (not shown) having an inner diameter smaller than the inner diameter of the resilient conductive element 204. The extension part may be integrally formed with the electrode body 202 or may be fixed to the electrode body 202. This structure allows the electrode body 124 of FIG. 1 to be used in the torch 240 of FIG. 2B, for example.

In some embodiments, the portion 220 of the power contact 206 has a tapered or truncated cone shape along the longitudinal axis A. FIG. In some embodiments, the electrode body 202 passes through (eg, passes through) the radially extending shoulder by including a radially extending shoulder (not shown) having a diameter greater than the inner diameter of the resilient conductive element 204. By moving the resilient conductive element toward the distal end 212 of the electrode body, the resilient conductive element 204 is released from the electrode body 202 and does not move axially toward the adjacent end 210. Do not let it.

In some embodiments, the distal face (not shown) of the shoulder is the reaction surface of the electrode body 202. Similar diameter interference fits can be used for the power contacts 206. For example, the resilient conductive element 204 crosses the surface 214 opposite the portion 220 by axially moving away from the electrode body 202 past the surface 214 of the power contact. ) Prevents release of the resilient conductive element 204 from the power contact. In some embodiments, the interface between the face 222 and the elastic conductive element 204 constitutes a current path from the power contact 206.

In some embodiments, the resilient conductive element 204 is disposed apart from the distal end 212 of the electrode body 202 instead of the adjacent end 210. The distal end 212 typically includes a light emitting device (not shown), such as hafnium, for more efficient plasma arc generation and workpiece processing. In some embodiments, the resilient conductive element 204 is integrally formed with the electrode body 202 or the power contact 206. For example, the elastic conductive element 204 may be formed of the same material as the electrode body 202. In another embodiment, the resilient conductive element 204 is bonded or secured to the electrode body 202 such that the electrode body (under normal operating conditions (eg, influence of gas pressure and / or gravity or other forces)) Prevent release from 202).

FIG. 2B is a cross-sectional view of a preferred contact initiated plasma arc torch employing the components and concepts of FIG. 2A. The structure of FIG. 2B shows the torch 240 before pilot arc operation. The torch 240 includes the electrode body 202 of FIG. 2A, the elastic conductive element 204 and the power contact 206 mounted within the torch body 242. Nozzle 244 and swirl ring 246 are also mounted to the torch body 242. The power contact 206 is fixedly positioned relative to the movable electrode body 202. The power contact 206 is located opposite the distal end 212 of the electrode body 202 (eg, the rear end of the torch 240). The distal end 212 of the electrode body 202 includes a light emitting element 248 that is substantially aligned with the outlet orifice 250 of the nozzle 244. In some embodiments, the light emitting element 248 and the outlet orifice 250 are approximately aligned about the longitudinal axis A. FIG. The swirl ring 246 is positioned to partially limit radial movement of the electrode body 202 in the torch body 242. For example, the vortex ring 246 can be fabricated to allow a relatively small gap between the vortex ring 246 of the electrode body 202 and one or more radial fins 252.

The elastic conductive element 204 is configured to react with the reaction surface 108 of the electrode body 202 and the surface 214 of the power contact 206 to electrically couple the electrode body 202 to the nozzle 244 Pressurized to contact. Gas flows into the plasma chamber 254 formed between the electrode body 202 and the nozzle 244, and a pilot current goes from the power source (not shown) to the power contact 206.

The gas pressure increases in the plasma chamber 254 until it is sufficient to overcome the force provided by the elastically conductive element 204. The gas pressure moves the electrode body 202 away from the nozzle 244 and makes contact with the power contact 206. The electrode body 202 moves substantially along the longitudinal axis A. As shown in FIG. As the electrode body 202 is moved away from the nozzle 244 by gas pressure, an arc is created and initiated in the plasma chamber 254. The arc ionizes the gas in the plasma chamber 2544 to form a plasma arc or jet that exits the orifice 250 of the nozzle and is transported to a workpiece (not shown).

The elastic conductive element 204 is constructed and designed to pass almost all pilot current between the power contact 206 and the electrode body 202. The resilient conductive element 204 may be formed of a material that facilitates the transfer of loads associated with the initiation of the current or pilot arc and dissipation of heat associated with the current to prevent the resilient conductive element from melting during pilot arc operation. . In some embodiments, the material of the resilient conductive element 204 is selected based on, for example, the rated current of the material. In some embodiments, the resilient conductive element 204 is the lowest resistance and / or highest conductance path between the power contact 206 and the electrode body 202. In addition, the mechanical properties of the resilient conductive element 206 facilitate the movement of the electrode body to initiate contact of the plasma arc torch. In some embodiments, the elastic element helps to align the electrode body with respect to the torch.

The resilient conductive element 204 may be an electrically conductive spring capable of reliably conducting a current of approximately 31 amps up to approximately 5 seconds or more for pilot arc operation without melting the spring or changing its mechanical properties. In some embodiments, the resilient conductive element 204 is made of Inconel (R) X-750 alloy. In some embodiments, the resilient conductive element 204 is made of stainless steel. For example, the resilient conductive element 204 may be formed of 17/4 precipitation hardened stainless steel wire (according to AMS5604) or Type 302 stainless steel wire (according to AMS5866 or ASTM A 313). In some embodiments, the resilient conductive element 204 is formed of wire approximately 0.73 mm (approximately 0.03 inches) in diameter and has an outer diameter of approximately 300/1000 (approximately 0.3 inches) and an outer diameter of approximately 12.7 mm Defines the length along the longitudinal axis (A).

In some embodiments, the resilient conductive element 204 is coated or plated with silver or silver alloy to allow for reduced electrical resistance and / or improved electrical conductance. Although shown is a helical compression spring, the resilient conductive element 204 has other structures, such as corrugated spring washers, finger spring washers, curved spring washers, crest-to-crest flat wire compression. Spring, or slotted conical disks. For example, springs of this type are described in US Pat. No. 5,994,663, which was assigned to Hypertherm, Hannover, New Hampshire, USA, the contents of which are incorporated herein by reference. Other spring structures also fall within the scope of the present invention.

In some embodiments, the resilient conductive element 204 is a wire disposed at an adjacent end 210 of the electrode body 202, and a second resilient element (not shown) is a distal end of the electrode body 202. Is placed on. The second elastic element presses the electrode body to the distal end 202 during pilot arc operation and limits radial movement of the electrode body 202 during torch operation (eg, during pilot arc operation and workpiece processing). do. In this manner, the second elastic element aligns the electrode body 202 during torch operation.

2C is a cross-sectional view of the plasma arc torch of FIG. 2B during the transferred arc mode. The contact surface 216 of the electrode body 202 is coupled in electrical communication with the corresponding surface of the power contact 206 in a substantially planar contact with the electrical contact (eg, the current is in contact with the contact surface 216). And between the electrode body 202 and the power contact 206 at the interface of the corresponding surface 218). When the contact surface 216 of the electrode body 202 is in contact with the corresponding surface of the power contact 206, the current path allows a current to pass directly between the power contact 206 and the electrode body 202. It is composed. In some embodiments, the resilient conductive element 204 no longer carries a significant amount of current after the electrode body 202 is moved in contact with the power contact 206. In this embodiment, the resilient conductive element 204 transfers current during initiation of the pilot arc, but not during the entire period of pilot arc operation. In some embodiments, the resilient conductive element 204 continues to carry current during the entire period of pilot arc operation.

When the arc is delivered to the workpiece, the cutting current is supplied to torch 240 (eg, during the transferred arc mode). In some embodiments, the resilient conductive element 204 does not carry a significant amount of current during the transferred arc mode. In particular, the current path between the power contact 206 and the electrode body 202 is lower than the current path from the power contact 206 through the elastic conductive element 204 to the electrode body 202 and And / or have high conductance. The design shown in Figures 2A, 2B, and 2C has two functions: pushing the electrode body 202 to the nozzle 244 and providing a current path between the power contact 206 and the electrode body 202 The ability to provide a single part reduces the number of consumable parts and simplifies torch design.

Previous torch designs, such as the example disclosed in US Pat. No. 4,791,268, assigned to Hyertherm, Hannover, New Hampshire, USA, employed a spring to provide mechanical force to press various torch parts. These torch designs also employed electrical components (eg, non-elastic wires) to provide current for pilot arc operation and transferred arc operation. These designs require the wire as the primary current path and have a relatively large diameter to easily pass current (eg up to approximately 200 amps) without melting the wire during transferred arc operation.

In some embodiments, the resilient conductive element 204 is a conductive wire or metal strip for passing a current between the power contact 206 and the electrode body 202 during pilot arc operation. The electrode body 202 is in a blown-back state (eg, the surface 216 of the electrode body 202 is in physical contact with and electrically in contact with the surface 218 of the power contact 206). Almost all currents that maintain the plasma arc in the transferred arc mode pass directly between the surface 216 and the surface 218. In more detail, when the surfaces 216 and 218 are in physical contact, the current path between the surface 216 and the surface 218 results in lower resistance and / or higher conductivity than the elastic conductive element 202. Can have This design employing a wire instead of a spring as the resilient conductive element 204 allows the wire to have a smaller diameter and increased flexibility as compared to the plunger wire of U.S. Patent No. 4,791,268. Smaller wires are also possible because the resilient conductive element 204 of FIGS. 2A, 2B and 2C does not carry all the current associated with the transferred arc operation.

In some embodiments, the resilient conductive element 204 is a conductive sleeve that allows pilot arc current to pass through and through the power contact 206 and the electrode body 202. For example, such a sleeve can be designed to be in close contact over the adjacent end 210 of the electrode body 202 and over the portion 220 of the power contact 206. In some embodiments, a second elastic element (not shown), such as a spring, may be connected with the sleeve to provide a mechanical function to press the electrode body 202 toward the nozzle 244.

In some embodiments, the power contact 206 and the resilient conductive element 204 are mounted to the torch body 242 and fixed relative to the movable electrode body 202. For example, when the nozzle 244 is separated from the torch body 242, the resilient conductive element 204 may replace the electrode body 202 with the torch body 242 (eg, the electrode body). 202 is discharged), and the current path between the elastic conductive element 204 and the electrode body 202 is broken. In this embodiment, the electrode body 202 is a consumable part of the torch 240. In other embodiments, the combination of the electrode body 202 and the resilient conductive element 204 may be sold or purchased together as a consumable part of the torch 240, eg, as a package.

3A is a cross-sectional view of a preferred embodiment of an electrode used in a contact initiated plasma arc torch. The electrode 300 includes an elongated electrode body 302 oriented along the longitudinal axis A. As shown in FIG. The electrode body 302 is formed of tellurium copper, silver, a silver copper alloy, or other alloy. The electrode body 302 includes an end portion 304 including an aperture 306 for receiving a light emitting element (not shown) and an adjacent end 308. The light emitting element can be formed, for example, of hafnium and is used to extend the operating life of a plasma arc torch (not shown) and to reduce wear on the electrode body 302. During operation of the plasma arc torch and processing of the workpiece, the distal end 304 of the electrode body 302 is located near the workpiece (not shown), and the adjacent end 308 is located away from the workpiece. The electrode body 302 is movable along the longitudinal axis A when the electrode 300 is mounted in the torch.

The electrode 300 includes an electrically conductive elastic element 310 (referred to herein as an elastic conductive element 310). The resilient conductive element 310 is configured to pass almost all pilot arc currents between a power source (not shown) and the electrode body 302 during pilot arc operation. The elastic conductive element 310 is shown as a helical spring that engages a radially extending flange 312 (eg, a shoulder) disposed on an adjacent end 306 of the electrode body 302. The flange 312 may be a reaction surface of the elastic conductive element 310. Physical contact between the elastic conductive element 310 of the electrode body 302 and the flange 312 provides a current path.

In some embodiments, the resilient conductive element 310 is secured to the electrode body 302 by being secured to the flange 312 (e.g., by soldering or welding). The elastic conductive element 310 may be fixed by a diameter interference fit or other forms of friction joints. In some embodiments, the elastic conductive element 310 is integrally formed with the electrode body 302 (eg, the electrode body 302 and the elastic conductive element 310 are made of the same piece of material). Manufactured). The elastic conductive element 310 is fixed relative to the electrode body 302 to prevent releasing the elastic conductive element 310 from the electrode body 302 during processing or maintenance operations.

As shown, the electrode body 302 includes a series of fins 314 integrally formed with the electrode body 302. The fins 314 increase the surface area of the electrode body 302 to function as a heat transfer surface to cool the electrode body 302 during torch operation. The fins 314 move the electrode body 302 along the longitudinal axis A by causing the plasma gas introduced into the plasma chamber (eg, the plasma chamber 254 of FIG. 2B) to rise to a sufficient gas pressure. A seal shape is formed to move to the adjacent end portion 308. As described above, the movement of the electrode body 302 toward the adjacent end portion 308 is such that a pilot arc current causes the elastic conductive element 310 to move. And the pilot arc when passed between the electrode body 302.

The placement of the pins 314 provides a spiral groove formed axially along the electrode body 302. Preferred pins are described in US Pat. No. 4,902,871, assigned to Hypertherm, Hannover, New Hampshire, the contents of which are incorporated herein by reference. The pins 314 are shown extending radially from the longitudinal axis A. FIG. Other structures of the fins 314 may extend longitudinally along the axis A, for example, as described in U.S. Patent No. 6,403,915, assigned to Hypertherm, Hannover, New Hampshire, The contents are incorporated herein by reference. Some embodiments of the electrode 300 do not include the fins 314 and the gas pressure forces the other surface of the electrode body 302 to move the electrode body during initiation of a pilot arc.

The electrode 300 includes a contact element 316 including a first surface 318 and a second surface 320. The first surface 318 is configured to be in electrical communication with a power source (not shown). For example, the first surface 318 may be in contact with the corresponding surface of the power contact (eg, the power contact 206 of FIG. 2A rather than FIG. 3A). The power supply may provide a current to the contact element 316 through the power contact. The second surface 320 is configured to be in electrical communication with the corresponding contact surface 322 of the electrode body 302 after the start of the pilot arc and during the transferred arc mode. In some embodiments, the first surface 318 of the contact element 316 is such that when the electrode 300 is mounted in the torch (eg, the first surface 318 is in contact with the power contact). Physical bonds or contact) are almost fixed. The contact element 316 may be formed of a relatively hard electrically conductive material, for example, stainless steel, chromium copper, nickel, or beryllium copper. In some embodiments, the contact element 316 is formed of a harder material than the material forming the electrode body 302. In some embodiments, the contact element 316 is coated with a relatively rigid electrically conductive material.

As shown, the resilient conductive element 310 is external to the adjacent end 308 of the electrode body 302 and engages with the second surface 320 of the contact element 316. Other structures that provide a current path from the contact element 316 through the elastic conductive element 310 to the electrode body 302 are also within the scope of the present invention. In some embodiments, a second conductive element (not shown) is provided between the contact element 316 and the electrode body 302 having a lower resistance and / or higher conductivity than the elastomeric conductive element 310, To provide. In this embodiment, the elastic conductive element 310 presses the electrode body away from the contact element 316 (eg, performs a mechanical function), but does not carry a significant amount of pilot current. In some embodiments, the resilient conductive element 310 is fixed to the contact element 316 (eg, by soldering or welding) or is integrally formed with the contact element 316. In some embodiments, the resilient conductive element 310 may be disposed between the second surface 320 of the contact element 316 and the corresponding contact surface 322 of the electrode body. In some embodiments, the first surface 318 of the contact element 316 couples with the elastic conductive element 310.

The electrode body 302 described above includes a receptacle 324 disposed at a proximal end 308 of the electrode body 302 and separated from the hole 306 at the distal end 304 by the electrode body 302 (For example, neither the hole 306 nor the receptor 324 is a through-hole). In some embodiments, the receptor 324 is nearly aligned with the axis A and defines an interior surface 326. The contact element 316 includes a connecting member 328 extending from the second surface 320. In some embodiments, the connecting member 328 slidably engages with the electrode body 302. For example, the connecting member 328 includes an alignment portion 330 which is substantially coaxial with the longitudinal axis A. FIG. The alignment unit 330 may be slidably coupled to the inner surface 326 of the receptor 324. In some embodiments, the engagement between the alignment portion 330 and the inner surface 326 limits the radial movement of the electrode body 302 or the contact element 316 in the torch.

The receptor 324 prevents release of the contact element 316 from the electrode body 302. The electrode body 302 includes a confinement surface 332 disposed at an adjacent end of the receptor 324 that reacts to a portion of the contact element 316 to prevent release. In some embodiments, the confinement surface 332 reacts (eg, by diameter interference fit) to the connecting member 328 or the alignment portion 330 of the contact element 316. In some embodiments, the confinement surface 332 includes an annular or ring-shaped structure. The confinement surface 332 is disposed within the receptor 324 such that the confinement surface does not interfere with the second surface 320 of the contact element 316 or that it is in contact with the contact surface 322 of the electrode body 302. Avoid physical contact in a nearly flat manner.

In some embodiments, the first surface 318, the second surface 320, or both are coated with silver or silver alloy to provide current flow between the power source and the electrode body 302 (eg, By reducing the electrical resistance at the surfaces 318, 320 of the contact element 316). In some embodiments, the slidable coupling between the contact element 316 and the electrode body 302 provides a current path of lower resistance and / or higher conductivity than the elastic conductive element 310. In this embodiment, the elastic conductive element 310 presses the electrode body away from the contact element 316 (eg, performs a mechanical function) but does not transmit a significant amount of pilot current. In more detail, the connecting member 328 or the alignment portion 330 forms a relatively low resistance path of current and is relatively rigid enough to pass through the receptor 324 to the electrode body 302, for example. Can be made to tolerance. Relatively tight tolerances are required to prevent ionization or formation of arcs in the space between the connecting member 328 or alignment 330 and the receptor 324.

3B is a detailed view of the components of the electrode of FIG. 3A prior to assembly. 3B is a detailed view of the proximal end 308 of the electrode body 302. In the illustrated embodiment, the electrode body 302, the elastic conductive member 310, and the contact element 316 do not form an integral assembly. In particular, the contact element 316 (e.g., the connecting member 128 and the alignment portion 130) is the elastic conductive element 310 and the electrode body 302 (e.g., the receptor 324 Can be released freely from In some embodiments, the length of the connecting member 328 and the alignment portion 330 does not exceed the depth of the receptor 324 such that the contact element is at the bottom surface 334 of the receptor 324. Do not "bottom out" the

Adjacent end 308 of the electrode body 302 may define a lip 336 adjacent to the receptor 324 extending along the longitudinal axis A along the axial direction. The lip 336 may be formed of the same piece of material as the electrode body 302. In some embodiments, the contact element 316 is fixed relative to the electrode body 302 (eg, the electrode body 302 releases the contact element 316 from the electrode body 302). To prevent). For example, the connecting member 328 and the alignment portion 330 may be located in the receptor 324. The contact element 316 is pressed against the electrode body 302 such that the second surface 320 physically contacts and moves in contact with the contact surface 322 of the electrode body 302. A second surface 320 of) engages with the lip 336.

Coupling between the second surface 320 and the lip 336 deforms the lip 336 into an adjacent receptor 324 such that the second surface 320 and the electrode body 302 of the contact element 318. Enable physical facing contact between contact surfaces 322. The deformed lip 336 may form the limiting surface 332 of FIG. 3A. In some embodiments, the contact surface 316 is pressed against the electrode body 302 while the light emitting element is disposed in the aperture 306. For example, during a process known as swaging, the force along the longitudinal axis A is applied to the light emitting element (eg, toward the adjacent end 308 of the electrode body 302). Is applied to fix the light emitting element in the hole 306. During swaging, an oppositely oriented force (eg toward the distal end of the electrode body 302) forces the contact element towards the adjacent end 308 of the electrode body 302 to cause the lip 336 to swell. To transform. In some embodiments, the applied force is approximately 4,450 N of force (eg, approximately 100 lbs of force). In some embodiments, after swaging, the confinement surface 332 may have a force of approximately 356 N (eg, such that the contact element 316 is released from the electrode body 302) before failure (eg, Strength of about 80 lbs).

In some embodiments, the resilient conductive element 310 may be positioned between the electrode body 302 (e.g., in physical contact with the flange 312) and the contact element 316 ) (Eg, in physical contact with the second surface 320). The elastic conductive element 310 can be “captured” between the contact element 316 and the electrode body 302. The confinement surface 332 is the slidingly mounted contact element 316. ) May be released from the electrode body 302. In some embodiments, the electrode 300 may be assembled before being used in a plasma arc torch, and may be packaged as an integral assembly.

In some embodiments, the confinement surface 332 has an annular structure (eg, when the lip 336 extends axially along a longitudinal axis A about the circumference of the receptor 324). Has In other embodiments, the confinement surface 332 is formed along a portion of the circumference of the receptor 324 that is less than the entire circumference. The connecting member 328 or the alignment portion 330 can be freely inserted into the receiver 324 without interference with the confinement surface 336, but for example, about the longitudinal axis A Rotating the contact element 316 prevents release of the contact element 316 by forming an interference portion between the limiting surface 332 and the connecting member or the alignment portion 330.

4A is a cross-sectional view of a preferred contact initiating plasma arc torch. 4A may be referred to as a “forward” structure or “start” structure. The torch 300 includes a torch body 402 defining a gas inlet 404. The torch 400 ) Includes a power contact 406 in electrical communication with a power source (not shown) to provide current to the power contact 406. The torch 400 includes the electrode 300 of Figure 3A. The first surface 318 of the contact element 316 is configured to be in physical contact with and in electrical communication with the power contact 306. The resilient conductive element 310 is located away from the power contact 306 and the electrode body Pressure 302 is in physical contact with and electrically in contact with the nozzle 408. The electrode body 302 (eg, distal end 304 of the electrode body 302 cooperates with the nozzle 408). To form part of the plasma chamber 410. The nozzle 408 is a plasma arc Includes an exit orifice 412 for ejecting a jet (not shown) from the plasma chamber 410 and transferring it to a workpiece (not shown). The shield 414 is part of the torch body 402 It is mounted to a fixed cap 416 mounted on 418. The shield 414 includes an outlet port 420 adjacent to an outlet orifice 412 of the nozzle 408. The outlet port 420 So that the plasma jet is delivered from the torch 400 to the workpiece. The shield 414 is configured to allow the material dispensed during the workpiece processing to accumulate on the nozzle 408 such that the nozzle 408 or the electrode 300, Torch 400 also includes a vortex ring 422 defining one or more ports 424 that allow gas (not shown) to enter and exit the plasma chamber 410. It includes.

Pilot arc operation begins with the start of the pilot arc. Pilot current passes between the power supply and the power contact 406. The power contact 406 passes the pilot current across the interface between the power contact 406 and the first surface 318 of the contact element 316 to the contact element 316. The pilot current passes between the contact element 316 (eg, the second surface 320) and the elastic conductive element 310. The current then passes between the elastic conductive element 310 and between the electrode body 302 and the nozzle 408. Preferred currents suitable for use as pilot arc currents are approximately 22 to 31 amps. In some embodiments, the power contacts 406 are made of tellurium copper, brass, copper, or other materials suitable for passing current during pilot arc operation and transferred arc operation.

During pilot arc operation, gas enters torch 400 through inlet 404 defined by torch body 402. The gas follows the path 426 defined by the torch body 402. The vortex ring 422 allows one or more channels 428 to pass the gas from the passageway 426 to the space 430 defined by the vortex ring 422 and the exterior of the portion 418. Define. The gas flows into the plasma chamber 410 through the ports 424. The gas pressure in the plasma chamber 410 is increased until it is sufficient to move the pressure to overcome the force provided by the elastic conductive element 310 and to move the electrode body 302 away from the nozzle 408. Thereby creating a space or gap between the electrode body 302 and the nozzle 408. In some embodiments, gas in the plasma chamber 410 acts on the pins 314 of the electrode body 302 to direct the gas toward the proximal end 310 of the electrode body 302. Pressurized along (A). The electrode body 302 moves relative to the torch 400 almost along the longitudinal axis A. FIG. In some embodiments, the contact element 316 aligns the electrode body 302 by limiting radial movement of the electrode body 302 during pilot arc operation and transferred arc mode. As the electrode body 302 moves away from the nozzle 408, the relative potential increases between the electrode body 302 and the nozzle 408. The potential difference is such that an arc (not shown) causes a minimum resistance path within the current gap between the electrode body 302 and the nozzle 408 (eg, between the electrode body 302 and the nozzle 408). By ionizing). The arc ionizes the gas in the plasma chamber 310 to form a plasma jet for use in workpiece processing.

4B is a cross-sectional view of the plasma arc torch of FIG. 4A including an exemplary component after pilot arc initiation. The structure of FIG. 4B is called a “blown bag” structure since the electrode body 302 is separated from the nozzle 408. The electrode body 302 is moved along the axis A until the contact surface 322 of the electrode body 302 contacts the second surface 320 of the contact element 316. The first surface 318 of the contact element 316 maintains physical contact and electrical conduction with the power contact 406 which is fixed relative to the electrode body 302. In some embodiments, the period during which the electrode body 102 moves along the axis A is less than or equal to approximately 0.3 seconds. In some embodiments, the resilient conductive element 310 carries current within the blow-back structure (eg, during pilot arc operation and pilot arc initiation). In some embodiments, the resilient conductive element 310 carries current only during pilot arc initiation.

Generally, the arc is moved from the nozzle 408 to the workpiece (not shown) to process the workpiece by placing the torch 400 near the workpiece. The workpiece is held at a lower potential than the nozzle 408. In some embodiments, the arc is transferred during pilot arc initiation (eg, prior to the blow-back structure of FIG. 4B). An electrical lead (not shown) in communication with the workpiece may provide a signal to a power source (not shown) based on the transfer of the arc to the workpiece. When the electrode body 302 is a blow-back structure, the power supply provides an increased current (eg, cut current) for the torch 400. One example of a method of increasing the current for the torch is known as a “dual threshold,” which is disclosed in US Pat. No. 6,133,543, assigned to Hypertherm, Hannover, New Hampshire, USA. Is cited by reference.

The incision current can be, for example, about 100 to about 150 amps. The cutting current is related to the operation of the torch 400 in the transferred arc mode. In some embodiments, the amount of incision current provided depends on the composition of the workpiece or the physical properties of the workpiece (eg, thickness or cutting depth of the workpiece). In some embodiments, the conveyed arc mode is referred to as the arc being moved to the workpiece and the power source providing the incision current. In some embodiments, the conveyed arc current is referred to as the arc being conveyed to the workpiece.

When the electrode body 302 has a blow-back structure, the power supply provides current to the power contact 406, the contact element 316 and the electrode body 302. The power contact 316 remains relatively fixed with respect to the electrode body 302 and the power contact 406. In particular, the first surface 318 of the contact element 316 can be designed to remain in physical contact and electrical communication with the power contact 406 after the electrode 300 is installed in the torch 400. have. In some embodiments, the contact element 316 is fixed to the power contact 406 by, for example, a frictional junction such that gravity of the earth acting on the electrode body 302 causes the electrode 300. Is sufficient to separate it from the torch 400. Most of the wear on the electrode 300 is due to repeated contact and disconnection of the electrode body 302 and the contact element 316 during operation (eg, start and stop) of the torch 400. It occurs at the interface between the second surface 320 of the element 316 and the contact surface 322 of the electrode body 302. The design of the electrode 300 is such that the first surface 318 of the contact element 316 maintains contact with the power contact 406 so that between the power contact 406 and the first surface 318. Reducing the formation of arcs reduces the amount of wear on the power contacts 406. Formation of an arc between the power contact 406 and the first surface 318 can create surface defects that reduce the operational life of the power contact 406 and the electrode 300.

5A is a cross-section of a preferred electrode that includes a contact element and an elastic conductive element disposed within the receptor of the electrode body. The electrode 500 includes an electrode body 502 defining a distal end 504 and an adjacent end 506 disposed opposite along the longitudinal axis A. As shown in FIG. The distal end 504 defines a hole 508 for receiving the light emitting element 510. Adjacent ends 506 of the electrode body 502 define a cylindrically shaped receptor 512 about the longitudinal axis A. As shown in FIG. In some embodiments, a non-cylindrical receptor 512 may be used. The receptor 512 is separated from the hole 508 by the electrode body 502 (eg, the electrode body does not have a through hole). The receptor 512 defines a first contact surface 514 disposed at the bottom of the receptor 512. The contact surface 514 is formed to provide electrical and / or physical contact with the power contact (shown in FIG. 5B). The receptor 512 also defines a second contact surface 516.

The electrode 500 includes a contact element 518 and an elastic conductive element 520 disposed in the receptor 512. The contact element 518 defines a first surface 522 and a second surface 534. The second surface 524 is formed to respond to the elastic conductive element 520 and to the second contact surface 516 of the receptor 512. The elastic conductive element 520 reacts to the first contact surface 514 to press the electrode body 502 to contact a nozzle (not shown) when installed in the plasma torch. In some embodiments, the resilient conductive element 520 may respond to a third surface (not shown) within the receptor 512.

The contact element 518 defines an annular structure designed to surround the power contact. The annular structure provides an alignment 526 to limit radial movement of the electrode body 520 by reacting to the power contacts. The contact element 518 and the elastic conductive element 520 are fixed to the receiver 512 by a tapered portion of a diameter smaller than the diameter of the contact element 518. In some embodiments, the tapered portion 528 is such that the contact element 518 and the elastic conductive element 520 are not released from the electrode body 502 (eg, the acceptor 512). Is a limiting surface. For example, the combination of the tapered portion 528 and the limiting element 518 is prevented by a diameter interference fit such that the elastic conductive element 520 is not released from the electrode body 502. In some embodiments, the tapered portion 528 defines an annular structure. In some embodiments, the receptor 512 does not include a tapered portion 528, and the contact element 518 and the resilient conductive element 520 are not secured to the receptor 512.

5B shows the electrode of FIG. 5A disposed in the transferred arc mode. 5B is a detailed cross-sectional view of the adjacent end 506 and power contact 540 of the electrode body 502. The power contact 540 defines an axial extension 542 configured to interact with the contact element of the receptor 512 and the electrode 500. The axial extension 542 is a first contact surface 514 of the electrode body 502 (eg, defined by the receptor 512) and a first surface of the contact element 518. Define a first mating surface 544 and a second mating surface 546 for electrical conduction and / or physical contact with 522. The power contact 540 defines a seat portion 548 that is configured to correspond to the tapered portion 528 of the electrode body 502 to limit radial movement of the electrode body 502.

In some embodiments, the electrode body 500 is positioned in a torch such that the first surface 522 of the contact element 518 is in electrical communication with the second mating surface 546 of the power contact 540. Or physically bonded to form an interface that is relatively fixed to the electrode body 502 during torch operation. The second surface 524 of the contact element 518 is initially located away from the second contact surface 516 of the receiver 512, and the first mating surface 544 of the power contact is the electrode body ( It is located away from the contact surface 514 of 502.

During pilot arc operation, a pilot current passes between the power source (not shown) and the power contact 540. The pilot current passes from the power contact 540 to the contact element 518 and from the contact element 518 through the elastic conductive element 520 to the electrode body 502, thereby providing the elastic conductive element ( 518 carries almost the entire pilot arc current. As the electrode body 502 moves away from the nozzle (not shown) to create an arc, the second contact surface 516 contacts the second surface 524 of the contact element 516, The first contact surface 514 is in contact with the first mating surface 544 of the power contact 540. Nearly all incision currents pass from the power contact 540 through the contact element 516 to the electrode body 502 and directly to the electrode body. During transferred arc operation, the resilient conductive element 520 does not carry a significant amount of current.

In some embodiments, the first mating surface 544 or the second mating surface 546 passes almost all current to the electrode body 502 during transferred arc operation. Multiple corresponding surfaces 544 and 546 can reduce physical wear on the contact surface 514 of the electrode body 502 or the first surface 522 of the contact element 518. This structure reduces wear by reducing the mechanical loads associated with physical contact between the power contacts 540 and each of the contact elements 518 and the electrode body 502. Reduced wear can extend the life of the electrode 500.

6A is a cross-sectional view of a preferred electrode including contact elements and elastic conductive elements disposed at adjacent ends of the electrode body. The electrode 600 includes an electrode body 602 defining a distal end 604 and an adjacent end 606 disposed opposite along the longitudinal axis A. As shown in FIG. The distal end 604 defines a hole 608 for receiving the light emitting element 610. The electrode 600 includes a contact element 612 and an elastic conductive element 614. The contact element 612 is in electrical contact with a first contact element 616 and a corresponding surface 620 of the electrode body 602 for electrical and / or physical contact with a power contact (see FIG. 6B); And / or defines a second contact surface 618 for physical contact. Adjacent ends 606 of the electrode body 602 define contact surfaces 622 for electrical and / or physical contact with the power contacts. The electrode body 602 defines a reaction surface 624 that reacts with the elastic conductive element 614 to provide a pressing force on the reaction surface 624 and the electrode body 602. Adjacent ends 606 of the electrode body 602 have a first confined surface 626 that prevents release of the contact element 612 and the elastic conductive element 614 (eg, by diametric interference fit). define. In some embodiments, the electrode body 602 does not include the confinement surface 624, and the contact element 612 and / or the elastic conductive element 614 are released relative to the electrode body 602. It is possible. In some embodiments, the resilient conductive element 614 is secured to one or both of the electrode body 602 or the contact element 612.

The contact element 614 defines an annular structure and includes an alignment portion 628 that limits the radial movement of the electrode body 602. For example, the alignment portion 628 may interact with the axially extendable portion 630 of the adjacent end 606 of the electrode body 602. The portion 630 defines a diameter slightly smaller than the diameter of the alignment portion 628 such that the portion 630 slides along the longitudinal axis A with no significant radial variation with the alignment portion 628. can do.

6B shows the electrode of FIG. 6A disposed in the transferred arc mode. The structure of FIG. 6B includes a power contact 640 positioned relative to an adjacent end 606 of the electrode body 602. The power contact 640 is provided with an open hole 642 in which the adjacent end 606 of the electrode body 602 is advanced as the electrode body 602 moves away from the nozzle (not shown) under gas pressure. define. The opening 642 is adjacent to the receiver portion 644 which is approximately centered on the longitudinal axis A. FIG. The receiver portion 644 is in electrical contact and physical contact with the first contact surface 646 and the contact surface 622 of the electrode body 602 for electrical and / or physical contact with the contact element 612. Define a second contact surface for. The receiver portion 644 is sized to receive the contact element 612 and the elastic conductive element 614 in addition to a portion of the adjacent end 606 of the electrode body 602. In some embodiments, the receiver portion 644 is sized to receive only the adjacent end 606 of the electrode body 602.

During installation, the electrode 600 is electrically connected and physically in contact with the first contact surface 646 of the power contact 640 to the electrode body 602 during torch operation. It is positioned to form a relatively fixed interface. The second surface 618 of the contact element 612 is initially located physically spaced from the corresponding surface 620 of the electrode body, and the contact surface 622 of the electrode body 602 is initially the power It is located physically spaced from the first contact surface 648 of the contact 640.

During pilot arc operation, a pilot current passes between the power source (not shown) and the power contact 640. The pilot current passes from the power contact 640 to the contact element 612 and from the contact element 612 through the elastic conductive element 614 to the electrode body 602, thereby providing the elastic conductive element ( Let 614 carry almost the entire pilot arc current. As the electrode body 602 is moved away from the nozzle (not shown) to form an arc, the corresponding surface 620 is in electrical conduction and / or with the second surface 618 of the contact element 612. The contact surface 622 is in physical contact and the electrical contact and / or physical contact with the second contact surface 648 of the power contact. Nearly all incision currents pass from the power contact 640 through the contact element 612 to the electrode body 602 and directly to the electrode body 602. During transferred arc operation, the resilient conductive element 614 does not carry a significant amount of the current.

In some embodiments, the first mating surface 646 and the second mating surface 648 pass almost all current through the electrode body 602 during transferred arc operation. Multiple corresponding surfaces 646, 648 may reduce physical wear on the first contact surface 622 of the electrode body 602 or the first contact surface 616 of the contact element 612. This structure reduces wear by reducing the mechanical load associated with the physical contact between the power contact 640 and each of the contact elements 612 and the electrode body 602. Reduced wear can extend the life of the electrode.

7A shows a partial exploded view of a preferred contact element, elastic element, and power contact that embody the principles of the present invention. The two-piece power connection 700 includes a power contact 702, a contact element 704, and an elastic element 706, which are substantially aligned along the longitudinal axis A. As shown in FIG. The power contact 702 defines an opening 708 adjacent to a cavity 710 that receives an axial extension 712 of the contact element 704. The diameter of the portion 712 is slightly smaller than the diameter of the cavity 710. The second elastic element 714 is radially formed along the axial length of the portion 712 to provide sufficient friction against the cavity 710 such that the portion 712 and the contact element 704 may be Preventing release from the power contact 702 (eg, frictional junction) and limiting radial movement of the contact element 704. In some embodiments, the second elastic element 714 is made of Louvertac (TM) spring, such as beryllium copper, and sold by Tyco Electronics Corp. of Harrisburg, Pennsylvania, USA. Other copper alloys also fall within the scope of the present invention. In some embodiments, the second elastic element 714 is plated with a conductive metal, such as gold, silver, nickel or tin. In some embodiments, the second elastic element 714 is electrically conductive and passes a portion of the current supplied by a power source (not shown) between the power contact 702 and the contact element 704. . The elastic element 706 may pass a pilot arc current between the power supply and the electrode body during the start of a pilot arc.

The power contact 702 is adjacent to the opening 708 through which current passes through the first corresponding surface 718 of the contact element 704 when the first surface 718 is adjacent to the extension 712. Define surface 716. The contact element 704 also includes a second surface 720 positioned opposite the first surface 718 that reacts with the first elastic element 706. The contact element 704 includes a portion 722 extending in the axial direction from the second surface 720, by defining a diameter smaller than the inner diameter of the elastic element 706, the elastic element 706 is Surround portion 722. The portion 722 is configured to be in electrical contact with an adjacent end of a torch electrode body (not shown). The portion 722 defines an interface 724 and an end surface 726. In some embodiments, the interface 724, the end surface 726, or both engage mating surfaces of the electrode body. The elastic element 706 is coupled with the component 728. The component 728 is designed to react with a corresponding surface (not shown) of the electrode body to orient toward (eg, away from the power contact 700) an end portion (not shown) of the electrode body. Provides axial force. The gas pressure reacts against the gas reaction surface of the electrode body and overcomes the axial force, thereby providing a corresponding portion of the electrode body during arc operation with which the interface 724, the end face 726, or both are transferred. The electrode body is moved towards the adjacent end until it reacts.

In some embodiments, the component 728 is formed of the same material integrally with the elastic element 706. In some embodiments, the component 728 is formed of a separate component and / or other material that is secured to the elastic element 706. The component 728 is shown as an annular washer coupled with the elastic element 706. Other structures of the component 728, for example a circular plate or ring external to the adjacent axial outside of the elastic element 706 (e.g., the contact element 904 described below with respect to FIG. Similar) can be used. This structure allows the elastic element 706 to be hidden from each electrode body, thereby allowing the electrode body and the component 728 to move almost together with respect to the power contact 702. In more detail, the component 728 is fixed relative to the electrode body and is movable relative to the contact element 704 and the power contact 702.

In some embodiments, the first surface (not shown) of the component 728 faces the corresponding surface of the electrode body, and the second surface (not shown) of the component 728 is the contact element (not shown). Facing end face 726 of 704. During a transferred arc operation, the second surface of the component 728 is in physical contact with the end surface of the contact element 704, and the first surface of the component 728 is in physical contact with the electrode body from the power source. A current path is provided through the power contact 702 and the contact element 704 to the electrode body.

In some embodiments, the elastic element 706 is not electrically conductive and provides a current path to the component 728 during conductive element (not shown) pilot arc operation. The conductive element may be configured to electrically connect the component to the contact element 704 or the power contact 702, for example by soldering, welding or other electrical contact. 702) and a wire or conductive strip positioned between the conductive element.

During transferred arc operation, the transferred arc current passes through a physical contact between the contact element 704 (eg, via the interface 724, the end surface 726, or both) and the electrode body. Can be. This structure allows a relatively low rated current conductive element to be used to pass the pilot current to the electrode body, which allows a relatively small conductive element to be used. Small conductive elements are useful for reducing physical interference between the conductive element and the moving parts of the torch system (eg, the elastic element 706 and the electrode body). Nearly all rated currents (eg, pilot currents and transferred arc currents) pass through the component 728 to the electrode body.

FIG. 7B shows the component of FIG. 7A disposed in a plasma arc torch operation. FIG. The portion 712 of the contact element 704 is advanced into the cavity 710 and the second elastic element 714 reacts with respect to an inner surface (not shown) of the cavity 710. Release of 704 is prevented using friction. The first mating surface 718 of the contact element 704 rests or physically contacts the surface 716 adjacent the cavity 710 from the power contact 702 to the contact element 704. Provide a current path. In some embodiments, the contact element 704 or the elastic element 706 may be exchanged without replacing the power contact 702. The interface between the power contact 702 and the contact element 704 (eg, the interface between the surface 716 and the corresponding surface 718) is fixed relative to the power contact 702 and the power Contact 702 does not wear out as quickly as in a structure in which the current path and the physical interface occur simultaneously. In some embodiments, the contact element 704 and the power contact 702 may form an integral body (eg, made of the same piece of material, rather than two separate pieces). The structures of FIGS. 7A and 7B can be employed in current contact initiating plasma arc torch, for example, replacing the integrated power contact 108 with a two-piece power connection 700 as shown in FIG. 1. In this case, the power connection unit 700 may be easily configured by replacing the electrode block 116. The power connection unit 700 may be relatively fixed to the electrode body by, for example, a clip or a pin as described above.

8A is a cross-sectional view of another embodiment of an electrode body, an elastic conductive element, and a contact element before installation in a plasma arc torch. The electrode 800 includes an electrode body 802, a contact element 804 and an elastic conductive element 806, which are approximately aligned with respect to the longitudinal axis A. FIG. 8A shows an adjacent end 808 of an electrode 800 that may be disposed within a plasma arc torch (not shown). The electrode body 802 is characterized by a shoulder 810 extending radially from the electrode body 802. The shoulder 810 defines a first surface 812 and a second surface 814. In some embodiments, the first surface 812 acts as a confining surface to contact the mating surface 816 of the contact element 804 and the contact element 804 is in axial force (eg, elastic). Preventing release from the electrode body 802 in the presence of conductive element 806, gas pressure, or in some cases provided by gravity. The second surface 814 of the shoulder 810 is configured to engage with the surface 818 of the elastic conductive element 86 to form a reaction interface.

The contact element 804 defines a first surface 820 and a second surface 822. The first surface 820 is designed or configured to seat or mate with a corresponding surface (not shown) of a power contact (not shown) to establish physical contact and electrical conduction. The second surface 822 of the contact element 804 is designed or configured to correspond to the surface 826 defined by the electrode body 802. In some embodiments, the resilient conductive element 806 is coupled with the second surface 822 of the contact element 804 to provide an axial force. The contact element 804 defines a receptor 828. The receptor 828 is formed to a size such that the elastic conductive element 806 is disposed about a portion of the electrode body 802 and disposed within the receptor 828 of the contact element.

In some embodiments, during pilot arc operation, the first surface 820 of the contact element 804 is in electrical conduction (and / or physical contact) with the power contact. The power contact provides a current to the first surface 820 that is transported across the contact element 804 to the second surface 822. Current may pass between the contact element 804 and the elastic conductive element 806 via an interface between the elastic conductive element 806 and the second surface 822. The elastic conductive element 806 provides a current path for passing a current between the power contact and the electrode body 802. For example, a current passes between the electrode body 802 and the elastic conductive element 806 at the interface between the surface 818 of the shoulder 810 and the corresponding second surface 814. In general, the receptor 828, the elastic conductive element 806 and / or the surface 812 cooperate to radially move the electrode body 802 when the electrode 800 is mounted to the plasma arc torch. To limit.

8B shows the structure of the component of FIG. 8A during the transferred arc mode. During the pilot arc mode, gas pressure responds to the electrode body 802 to overcome the pressing force of the elastic conductive element 806 in a direction axially away from the adjacent end 808 so that the electrode body 802, In particular, the surface 826 is moved into contact with the corresponding second surface 822 of the contact element 804. In this structure, electrical conduction can be established directly between the contact element 804 and the electrode body 802, and the current can be increased for transferred arc operation. In some embodiments, the contact element 804 defines an end surface 840 away from the surface 842 of the electrode body 802. In some embodiments, the end surface 840 contacts or “bottoms out” by reacting against the surface 842 to provide a second current path between the contact element 804 and the electrode body 802. do.

9 is a cross-sectional view of another embodiment of an electrode embodying the present invention. The electrode 900 includes an electrode body 902, a contact element 904 and an elastic conductive element 906, which are approximately aligned along the longitudinal axis A. As shown in FIG. The electrode body 902 may react with the surface 910 of the elastic conductive element 906 to prevent (eg, capture) release of the elastic conductive element 906 from the electrode body 902. Define a reflective image extending surface 908. The elastic conductive element 906 or surface 910 may be axially advanced along the longitudinal axis A to be pressed or compressed on the surface 908 to form a radial interference fit. Other ways of bonding may be used to prevent release of the resilient conductive element 906 from the electrode body 902.

The contact element 904 is a first surface 914 in electrical contact and / or physical contact with a receiver 912, a corresponding surface of a power contact of a plasma arc torch (not shown), and the electrode body 902. Defines a second surface 916 that is in electrical contact and / or physical contact with a corresponding surface 918. The receptor 912 may be formed such that the inner diameter of the receptor is slightly smaller than the outer diameter of the elastic conductive element 906. The contact element 904 and the receptor 912 are compressed or pressed across the elastic conductive element 906 to provide a frictional or other manner between a portion of the elastic conductive element 906 and the receptor 912. Establish a junction. In some embodiments, optional or additional joints or junctions may be used to secure the contact element 904 to the resilient conductive element 906 and the electrode 900. Generally, the receptor 912 cooperates with the elastic conductive element 906 to radially limit the electrode body 902 when the electrode 900 is mounted within the plasma arc torch.

10A is a perspective view of a preferred contact element and an elastic conductive element embodying the principles of the present invention. The system 100 includes a contact element 1002 and an elastically conductive element 1004 disposed within the receptor 1006 of the contact element 1002. The contact element 1002 includes a flange 1008 defining one or more through holes 1010 to facilitate the passage of gas about the system 100. In some embodiments, the through hole 1010 imparts vortex movement to the gas as the gas moves about the electrode body, for example to cool the electrode body or the plasma arc torch. In some embodiments, the elastic conductive element 1004 is fixed or fastened (eg, by adhesion) to the contact element 1002. In some embodiments, the elastic conductive element 1002 is integrally formed with the contact element 1002.

10B is a partial cross-sectional view of the plasma arc torch employing the components of FIG. 10A during pilot arc operation. The torch 1020 includes the contact element 1002, the elastic conductive element 1004, the electrode body 1022, and the power contact 1024, which are substantially aligned along the longitudinal axis A. FIG. In some embodiments, the power contact 1024 is in electrical contact with a power source (not shown). The power contact 1024 is surrounded by a torch component 1026 that defines a gas passage 1030 in cooperation with the outer surface 1028 of the contact element 1004. The gas may be supplied for the plasma arc generation and workpiece processing described with reference to FIG. 2A. Gas pressure in the torch 1020 is directed towards the power contact 1024 around the electrode body 1022 (eg, by swirling around the electrode body 1022 guided by the pins 1032). Reduced by flow. Gas may flow through the hole 1010 away from the electrode body 1022 along the gas passage 1030 in the contact element 1004.

In the illustrated embodiment, the flange 1008 is disposed between the surface 1034 of the torch component 1026 and the surface 1036 of the swirl ring 1038. In some embodiments, the system 1000 of FIG. 10A is a consumable component, installed in the torch 1020, and the electrode body 1022 is replaced more frequently than the system 1000. This allows for example to be easily replaced without disassembling the torch 1020 after the electrode body 1022 is exhausted. In some embodiments, the system 1000 is secured relative to the power contact 1024 by an interference fit. For example, the system 1000 is located within the torch 1020, and the vortex ring 1038 is secured (eg, screwed) to the outer surface 1040 of the torch component 1026 so that the A flange 1008 secures axially and / or radially to the torch component 1026, the power contact 1024 and / or the torch 1020. In some embodiments, the flange reacts with or rests against another component of the torch 1020.

One or more components of the system 1000 may be integrally formed with the vortex ring 1038. For example, the flange 1008 may be bonded or otherwise secured to the vortex ring 1038 to form an integral component. In some embodiments, the contact element 1002 is formed of the same material as the vortex ring 1038 during processing or manufacturing. The elastic element 1004 may be fixed to the contact element 1002-vortex ring 1038 combination by, for example, a diameter interference fit or other fixing method. In some embodiments, the elastic element 1004 is not fixed to either the contact element 1002 or the swirl ring 1038.

The electrode body 1022 is moved toward the power contact 1024 (eg, by gas pressure) such that the surface 1042 of the electrode body 1022 has a corresponding surface 1044 of the contact element 1002. ) To establish electrical conduction and physical contact. Current associated with the transferred arc operation of the torch 1020 passes between the electrode body 1022 and the contact element 1002.

11A shows a preferred contact element for use in a contact initiated plasma arc torch. The contact element 1100 includes a first surface 1102, a second surface 1104, an extension 1106, and a restriction 1108. The first surface 1102 is configured to be in electrical communication with a power contact of a plasma arc torch (not shown). For example, electrical conduction can be achieved by physical contact with a corresponding surface (not shown) of the power contact. The second surface 1104 is configured to be in electrical communication with an electrode body (not shown), an elastic conductive element, or both. For example, electrical conduction can be achieved through the electrode body by physical contact between the second surface 1104 and the corresponding surface of the electrode body. In some embodiments, the physical contact between the power contact and the first surface 1102 and the physical contact between the electrode body and the second surface are between the power contact (eg, a power source) and the electrode body. Establish a current path through

An extension 1106 of the contact element is adjacent to the restriction 1108. In some embodiments, the extension and the restriction are integrally formed (eg of the same material). The extension 1106 projects at right angles from the second surface 1104. As shown, the extension 1106 defines a circular cross section having a diameter, but other structures are possible. The width w of the restriction 1108 is greater than the diameter of the extension 1106, and the thickness t of the restriction 1108 is smaller than the diameter.

FIG. 11B shows the contact element of FIG. 11A rotated 90 degrees about a vertical axis. FIG. In some embodiments, the restriction 1108 and the extension 1106 advance into the receptor of the electrode body (not shown) in the first orientation as shown in FIG. 11B. An open hole adjacent the receptor is shaped to allow the restriction 1108 and the extension 1106 to enter the receptor. However, by rotating the contact element 1100 on a vertical axis (eg, as shown in FIG. 1A), the limiter 1108 acts on a portion of the receptor such that the contact element is removed from the electrode body. The contact element 1100 is positioned so as not to be released. The contact element 1100 may be fixed to the electrode body in another manner, for example, by screwing or an interference fit.

12A is a partial cross-sectional perspective view of an assembly 1200 for a contact initiated plasma arc torch. The assembly 1200 includes an electrode 1204, a hollow body 1208, an elastic element 1212, and a power contact 1216. The electrode 1204 includes an electrode body 1220 that includes an end portion 1224 that receives the light emitting element 1228. The electrode 1204 also includes an end 1232 positioned away from the distal portion 1224. The end 1232 is positioned relative to the distal end 1224 (eg, adjacent to the electrode body 1220). The electrode body 1220 includes a combination of helical grooves 1236 that direct gas flow and facilitate cooling of the assembly 1200. The electrode 1204 moves to slide along axis A, for example, with an inner surface 1240 of the hollow body 1208 when the assembly 1200 is installed in a torch (not shown). Can be. The hollow body 1208 includes a front portion 1244 and a rear portion 1248. In one embodiment, the front portion 1248 includes one or more holes 1252 formed from the outer surface 1356 to the inner surface 1240. The holes 1252 may apply a vortex movement about the axis A to the gas flowing through the assembly 1200. The hollow body 1208 with these holes 1252 creating a vortex gas flow is commonly referred to as a vortex ring. It will be appreciated that the vortex ring is a simple variant of the hollow body 1208 and that the system disclosed herein can perform the function of the hollow body 1208 or the vortex ring structure. In addition, the hollow body may be an integral part of the torch.

An end 1232 of the electrode 1204 includes a portion 1260 extending axially along the axis A. As shown in FIG. The portion 1260 has a first length 1264 (or distance) along a first direction (eg, radially away from axis A), and a second direction (eg, the axis A). A second length 1268 (or distance) radially distant from and perpendicular to the first direction. The hollow body 1208 includes a shoulder 1272 disposed about the inner surface 1240 (eg, defined on the inner surface 1240). The shoulder 1272 may also be called contour, step, or flange, and may have various geometries (eg, semicircular, triangular, square, or non-polygonal) with respect to the inner surface. The shoulder 1272 defines a first portion 1276 and a second portion 1280. The first portion 1276 and the second portion 1280 cooperate to form an open hole in which the portion 1260 of the electrode 1204 can move. In detail, the second portion 1280 is located at a distance from the axis A sufficient to facilitate sliding of the second length 1268 therethrough. The first portion 1276 cooperates with the second portion 1280 to define an opening having a slot 1284 that is sufficiently larger than the first length 1264 to slide the first length 1264 therethrough. To facilitate passage. The electrode 1204 is installed in a torch in the hollow body 1208 so that the portion 1260 is defined by the first portion 1276 and the second portion 1280 in the axial direction along the axis A. FIG. It can be moved reciprocally through the opening hole.

The portion 1260 also includes a surface 1288, the surface 1288 being in contact with the first region 1290 and the power contact 1216 in electrical communication with the elastic element 1212, for example, A second area 1292 is in electrical communication with the corresponding surface 1294 of the power contact 1216. The elastic element 1212 elastically presses the electrode 1204 toward the distal end 1224. The electrode 1204 is prevented from being discharged from the torch by the nozzle in physical contact with the distal end 1224 when a nozzle (not shown) is installed. The nozzle is secured to the torch such that the portion 1260 (eg, through the first region 1290) is in physical contact with the elastic element 1212. For example, by installing the nozzle, the portion 1260 is pressed through the slot 1284 and positioned so that the first region 1290 is in physical contact with the elastic element 1212. When the nozzle is installed, the elastic element is compressed.

The elastic element 1212 is located between the shoulder 1272 and the flange 1296 of the power contact 1216. The elastic element 1212 is fixed between the hollow body 1208 (eg, via the shoulder 1272) and the power contact 1216 (eg, via the flange 1296) or Is captured. The shoulder 1272 secures the elastic element 1212 and easily accesses the elastic element 1212 and the power contact 1216 by the electrode 1204.

The power contact 1216 is in electrical contact with a power source (not shown). During pilot arc operation, the power supply provides a pilot arc current to the power contact 1216, the current being from the flange 1296 through the elastic element 1212 to the first region 1290 of the electrode 1204. Flows up to). Plasma gas (not shown) flows around the electrode during pilot arc initiation, and the plasma gas increases the hydraulic pressure on the electrode 1204. The pressure physically contacts the electrode 1204 by moving it axially toward the power contact 1216. As the electrode 1204 and the nozzle are physically separated, a pilot arc is generated in a plasma chamber (not shown) formed between the nozzle and the electrode 1204. Pressure moves electrode 1204 to be in physical contact with and in electrical communication with power contact 1216 for transferred arc operation. When the electrode 1204 is in contact with the power contact, the portion 1260 is disposed in the slot 1284.

During transferred arc operation, the transferred arc current is transferred from the power source through the power contact 1216 to the electrode 1204 and the second region 1292 of the surface 1280 of the portion 1260 and the power contact ( Flows through physical contact between the corresponding surfaces 1294 of 1216. The gas pressure is increased during the transferred arc operation to form a plasma jet for processing the workpiece (not shown).

The assembly 1200 is shown as the first region 1290 is in direct physical contact with the elastic element 1212, although other configurations are possible. For example, the elastic element 1212 may include a discrete contact surface (not shown), such as an annular washer-shaped plate secured to the elastic element 1212 in physical contact with and electrically in contact with the electrode. Similarly, the corresponding surface 1294 of the power contact 1216 may be plated or coated with any material such that the electrode 1204 contacts the plating or coating rather than the power contact 1216 itself. Such structures fall within the scope of the present invention.

In some embodiments, the front portion 1244 and the rear portion 1248 of the hollow body 1208 are integrally formed (eg, made of the same piece of material). In some embodiments, the front portion 1244 and the rear portion 1248 may be formed of different materials, for example, the front portion 1244 may be formed of an insulating material. The rear portion 1248 may be formed of a conductive material.

In some embodiments, the slot 1284 is configured to facilitate angular displacement of the electrode 1204 about an axis A within the hollow body 1208 (eg, the portion 1260 may cause the Have a dimension or size significantly greater than the first length 1264) while being disposed within the slot 1284. The slot 1284 may resist the angular displacement of the electrode 1204 about the axis A, for example by reacting with respect to the portion 1260 to prevent angular displacement. In some embodiments, the first region 1290 and the second region 1292 of the surface 1288 are not coplanar and do not form regions of the same surface. For example, the first region 1290 is located axially spaced apart from the second region 1292 so that the portion 1260 of the electrode 1204 has an axial step, flange, or shoulder (not shown). May not be included).

12B is an exploded perspective view of the assembly 1200 of FIG. 12A, with a portion of the hollow body 1208 cut away. 12B shows the electrode 1204, the hollow body 1208, the elastic element 1212, and the power contact 1216, which are not assembled prior to installation in a plasma arc torch (not shown). Structure. During assembly, the electrode 1204 slidably engages with the hollow body 1208 such that no screwing is required to attach the electrode 1204 to the hollow body 1208. The surface 1297 of the elastic element 1212 is shown. The surface 1297 contacts the shoulder 1272 of the hollow body 1208 when the elastic element 1212 is positioned within the torch. The first region 1290 is moved through the slot 1284 to be in physical contact with and in electrical communication with at least a portion of the surface 1297 of the elastic element 1212.

12C is a top view of a portion of the assembly of FIG. 12A. 12C shows the surface 1297 of the hollow body 1208, the power contact 1216, and the elastic element 1212. Although the electrode 1204 is not shown, various features of the electrode 1204 as shown in FIG. 12A are incorporated by reference. The hollow body 1208 includes the shoulder 1272. The shoulder 1272 defines a first region 1276 and a second region 1280 that cooperate to form an open hole in which a portion 1260 of the electrode 1204 can move. As shown, the first region 1276 and the second region 1280 cooperate to form the slots 1284A, 1284B in the opening, where the electrode 1204 is installed in the torch. In this case, the portion 1260 of the electrode 1204 may move (for example, a reciprocating sliding movement). In this structure, the slots 1284A, 1284B in the hollow body 1208 have a complementary shape to the shape of the portion 1260 of the electrode. The shapes of the slots 1284A, 1284B are complementary in that they are formed to receive the portion 1260 of the electrode. However, the shape of the slots 1284A, 1284B need not match the shape of the portion 1260 of the electrode. Instead, the shape of the slots 1284A, 1284B may only allow for a gap in the portion 1260 of the electrode.

In some embodiments, the first portion 1276 and the second portion 1280 cooperate to form a contoured open hole with one slot 1284A or 1284B (but not both). Each slot 1284A, 1284B is defined by two portions 1285 parallel to each other. The portions 1285 may also define other structures and orientations. For example, the portions 1285 may be oriented radially with respect to the axis A (eg, forming a triangular slot 1284). The portions 1285 may be circular, semicircular, or other curved surface. In general, the portions 1285 are defined by (eg, the first portion 1276 and the second portion 1280) such that the portion 1260 of the electrode passes through the shoulder 1272. Through any open hole).

The distance d1 from the axis A to the second portion 1280 is greater than the distance d2 from the axis A to the first portion 1276. The distance d3 from the axis A to the elastic element 1212 is larger than the distance d2 and smaller than the distance d1. In some embodiments, the distance d3 may be less than the distance d2 (eg, an annular plate (not shown) is secured to the elastic element 1212). The distance d4 from the axis A to the power contact 1216 is smaller than the distance d3 to facilitate the passage of the second region 1292 through the elastic element 1212 and the power contact. It is in physical contact with and in electrical communication with a corresponding surface 1294 of 1216.

In some embodiments, the electrode 1204 does not move past the shoulder, for example, when the portion 1260 and the slots 1284A, 1284B are not aligned. In this structure, the portion 1260 contacts the shoulder 1272 and resists passage of the portion 1260 there through. In some embodiments, the electrode 1204 can be firmly located within the torch. For example, the portion 1260 may pass completely through the shoulder 1272 in contact with the elastic element 1212 (eg, through the first region 1290). The portion 1260 compresses the elastic element 1212. The elastic element 1212 presses the electrode 1204 toward the distal end 1224. Upon angular displacement of the portion 1260 about the axis A, an adjacent surface (not shown) of the shoulder 1272 resists distal movement of the electrode 1204. Adjacent surfaces of the portion 1260 and the shoulders 1272 prevent the elastic element 1212 from discharging the electrode 1204 from the hollow body 1208 and / or the torch.

In some embodiments, the portion 1260 has a circular structure about the axis A. In this embodiment, the portion 1260 may be connected to the first region 1290 (eg, an annular circumference of a circular structure) and the power contact 1216 that are in physical contact with and electrically communicate with the elastic element 1212. A second area 1292 (eg, an area disposed within the annular outer circumference) is in electrical contact and in physical contact. As mentioned above, the first region 1290 and the second region 1292 may be coplanar (eg portions of the same surface) or non-cavity plane (eg portions of other surfaces). Can be. In an optional embodiment, the first region 1290 is a separate radial location along the length of the longitudinal axis A of the electrode 1204, such as a pin extending radially through the electrode 1204. It may be an extension (not shown). The radial extension functions in the same manner as the first region 1290 by providing a mechanism for electrically coupling the electrode 1204 to the elastic element 1212 that carries a pilot arc. In one embodiment, the radial extension is a long shoulder or pin that can pass through the shoulder 1272 and still allow the elastic element to be retained in the hollow body 1208. In this embodiment, the shoulder 1272 further places the axial length of the hollow body 1208 towards the distal end of the electrode.

13A is a perspective view of an electrode 1300 of a contact initiating plasma arc torch. The electrode 1300 is similar to the electrode 1204 shown in FIG. 12A. The electrode includes a distal end 1304 and a second end 1308. The second end 1308 includes an extension 1312 extending axially along the axis A. As shown in FIG. The extension 1312 defines three portions 1316A, 1316B and 1316C (also called “fins”), all of which extend away from the axis A. Each of the three portions 1316A, 1316B, 1316C defines a first length l1 and a second length l2 greater than the first length l1. In some embodiments, the values of the first length l1 and the second length l2 of each of the three portions 1316A, 1316B, 1316C are the same. The values of the first length l1 and the second length l2 may be different for each of the three portions 1316A, 1316B, 1316C. The lengths l1 and l2 are shown to be oriented at right angles to one another. In some embodiments, the lengths l1 and l2 may be oriented in a different configuration, for example in a direction radially away from the axis A toward points 1320A and 1320B, respectively. Other directions of the length l1 and l2 are possible.

As shown, each of the three portions 1316A, 1316B, 1316C has an isometric structure (e.g., between each of the three portions 1316A, 1316B, 1316C) about the axis A. Are arranged as?)). However, each of the three portions 1316A, 1316B, 1316C may be disposed about the axis A in an angle structure other than conformal.

Each of the three portions 1316A, 1316B, 1316C each has a first surface 1324A, 1324B, 1324C for electrical conduction and / or physical contact with a corresponding surface (not shown) of an elastic element (not shown). Include. Each of the three portions 1316A, 1316B, 1316C each has a corresponding surface (not shown) of a power contact (not shown) and a second area 1328A, 1328B, 1328C for electrical conduction and / or physical contact, respectively. Include.

As shown, the first regions 1324A, 1324B, 1324C of each portion 1316A, 1316B, 1316C are shown coplanar with each of the second regions 1328A, 1328B, 1328C. In some embodiments, the first regions 1324A, 1324B, 1324C are not coplanar with each of the second regions 1328A, 1328B, 1328C. In some embodiments, the second regions 1328A, 1328B, and 1328C are not coplanar with each other second region. In some embodiments, a sub-combination of three parts, eg, 1316A and 1316B, is in electrical communication with the elastic element, while the other portion, 1316C, is not in electrical communication with the elastic element. The portions, for example 1316C, which are not in electrical communication with the elastic element, can provide alignment features or increased surface area to enhance cooling of the electrode. The portion 1316C may still be moved to be in physical contact with and in physical communication with the power contact during the transferred arc operation. In some embodiments, the first region 1324A, 1324B, 1324C or the second region 1328A, 1328B, 1328C, or both, may coincide with the extension 1312. For example, the pylon current and / or the transferred arc current can flow between the power source and the electrode 1300 (eg, through the sliding contact described above) through an electrical conduction with the extension 1312. .

FIG. 13B is a top view of the assembly 1340 used for the electrode of FIG. 13A. The assembly 1340 includes a hollow body 1344, an elastic element 1348, and a power contact 1352. The assembly is similar to the assembly 1200 shown in FIG. 12C. The assembly 1340 is configured for use with the electrode 1300 of FIG. 13A. In detail, the hollow body 1344 has a shoulder 1356 having a first portion 1360 and a second portion 1364 cooperating to form an open opening of a contour having three slots 1368A, 1368B, 1368C. It includes. The opening and the three slots 1368A, 1368B, and 1368C facilitate movement of the counterparts 1316A, 1316B, and 1316C through the opening and are in physical contact with and electrically in contact with the elastic element 1348. do. As described above, the size of slots 1368A, 1368B, 1368C is shown to have approximately the same size as the portions 1316A, 1316B, 1316C, while the slots 1368A, 1368B, 1368C have the corresponding portions 1316A. , 1316B, 1316C) (eg, may be larger in the circumferential direction).

14A, 14B, 15A, 15B and 16 illustrate optional embodiments of electrodes and assemblies that operate similarly to those described above.

14A is a perspective view of an electrode 1400 of a contact initiating plasma arc torch. The electrode 1400 includes four portions 1404A, 1404B, 1404C, 1404D.

14B is a top view of the assembly 1420 used for the electrode 1400 of FIG. 14A. The assembly 1420 includes a shoulder 1428 having a first portion 1432 and a second portion 1434 defining an open aperture of an outline having four slots 1440A, 1440B, 1440C, 1440D. The inclusion of a hollow body 1424 facilitates passage of the four corresponding portions 1404A, 1404B, 1404C, 1404D through the open opening of the contour and with the elastic element 1444 and the power contact 1482. Physical contact and / or electrical conduction.

15A is a perspective view of electrode 1500 of a contact initiating plasma arc torch. The electrode 1500 includes five portions 1504A, 1504B, 1504C, 1504D, 1504E.

FIG. 15B is a top view of assembly 1520 used for electrode 1500 of FIG. 15A. The assembly 1520 facilitates passage of the five counterparts 1504A, 1504B, 1504C, 1504D, and 1504E through the open openings of the assembly and provides physical contact with the elastic element 1532 and the power contact 1536. And / or electrical conduction. The electrode 1500 can be used in a similar manner as described for the electrode 1204 of FIG. 12A, the electrode 1300 of FIG. 13A, and the electrode 1400 of FIG. 14A.

The value of the operating current of the plasma arc torch is determined by the number of portions that a particular electrode comprises (eg, three portions 1316A-1316C in FIG. 13A, four portions 1404A-1404D in FIG. 14A, or FIG. 15A). Five portions 1504A-1504E). For example, an electrode with the three portions 1316A-1316C can be used for a torch operating at approximately 60 amps during a transferred arc operation. Electrodes with four portions 1404A-1404D can be used in a torch operating at approximately 80 amps during transferred arc operation. Electrodes with five portions 1504A-1504E can be used in a torch operating at approximately 100 amps during transferred arc operation. The electrodes employing the designs shown in FIGS. 13A, 14A, and 15A can be used for torch with open holes of the shape shown in FIGS. 13B, 14B, and 15B, respectively. In some embodiments, the electrode can include more than five portions.

By associating the number of pins with the torch operating current, the use of the correct electrode for a given operating current of the torch can be ensured. For example, in the operation of a 60 amp torch, the use of a hollow body 1344 with three slots 1368A, 1368B, 1368C may result in a corresponding number of portions (or “pins”), for example three. Sixty amperes having three portions 1316A-1316C. On the other hand, if the user wishes to use a 100 amp electrode, for example an electrode with five parts 1504A-1504E in a 60 amp torch with three slots 1368A, 1368B, 1368C, the electrode ( 1500 and the hollow body 1344 do not match. The five portions 1504A-1504E prevent passing through the three slots 1368A-1368C. By employing such a system, the specific torch can be optimized for a specific electrode. In some embodiments, the user is prevented from using an electrode having five pins (eg, electrode 1500), and the torch is removed from the electrode (eg, three slots 1368A-1368C). Having a torch) is not optimized. In addition, an electrode with smaller pins (eg, three portions 1316A-1316C (eg, the electrode 1300) has more slots (eg, five of the hollow body 1524). Prevents the use of a torch employing a slot, thereby increasing the operating life of the electrode by optimizing the amount of current flowing through the electrode.

16 is a perspective view of an electrode 1600 of a contact initiated plasma arc torch. The electrode 1600 includes a distal end 1604 and a second end 1608. The second end 1608 includes an extension 1612 that defines a surface 1616 having a diameter d1. Two regions 1620A, 1620B extend from the surface 1616 along axis A. FIG. Each of the regions 1620A, 1620B defines a respective end face 1624A, 1624B. The end faces 1624A, 1624B may be used to be in physical contact with and electrically in contact with a corresponding surface of the elastic element (eg, surface 1297 of the elastic element 1212 of FIG. 12C). Current for a pilot arc flows between the surface 1624A and 1624B and the regions 1620A and 1620B between the elastic element (not shown) and the electrode 1600. The surface 1616 is in physical contact with and in electrical communication with a corresponding surface (not shown) of a power contact (not shown), such as the surface 1294 of the power contact 1216 of FIG. 12A for transferred arc operation. do.

The regions 1620A and 1620B also define respective extending surfaces 1628A and 1628B. The regions 1620A and 1620B are slots 1284A and 1284B defined by the slots 1284A and 1284B (eg, the first portion 1276 and the second portion 1280 of the shoulder 1272 of FIG. 12C). The extensions 1628A and 1628B act on slots 1284A and 1284B to prevent or resist angular displacement of the electrode 1600 about the axis A in the torch. As shown, the regions 1620A and 1620B are substantially parallel to the axis A. Other structures or alignments of the regions 1620A and 1620B may be used. Each of the regions 1620A and 1620B. Defines a diameter d2 smaller than the diameter d1.

In some embodiments, a second extension (not shown) extends from the surface 1616 and defines a second surface (not shown). The second surface may be parallel to the surface 1616. The second extension extends to the distal end (eg, towards the distal end 1604) to define a cavity (not shown) in the second end 1608 relative to the surface 1616. The second extension extends adjacent (eg, away from the distal end 1604) to define a cylindrical or columnar portion. In this embodiment, the second surface may be in physical contact with and in electrical communication with a corresponding surface of the power contact for transferred arc operation.

The regions 1620A, 1620B are disposed radially opposite to each other and are equidistant from the axis A. FIG. In some embodiments, the electrodes 1600 are three used for the assemblies 1340, 1420, 1520 of two or more regions 1620A, 1620B (eg, FIGS. 13B, 14B, and 15B, respectively); Four or five areas). In some embodiments, the electrode 1600 includes only one region 1620A or 1620B. In this embodiment, the regions 1620A, 1620B may be parallel and aligned with respect to the axis A. FIG. The shoulder (eg, shoulder 1272, in this embodiment) may define an opening having a substantially continuous circumference (eg, without slot 1284). It is smaller than the outer diameter of the element and larger than the inner diameter of the elastic element so that the elastic element is not separated from the torch. This facilitates contact between the region 1620A or 1620B and the elastic element.

While the invention has been shown and described with reference to specific embodiments, it will be apparent to those skilled in the art that various changes in form and detail may be made without departing from the spirit and scope of the invention as defined by the following claims. It can be seen that it can be done without. For example, although several surfaces are shown as being flat, surfaces having non-planar structures such as spherical, hemispherical, conical, and / or cylindrical structures can be used without departing from the spirit and scope of the present invention.

Claims (71)

An electrode for plasma arc torch in electrical communication with a power source, The electrode for the plasma arc torch is movable relative to the nozzle in the plasma chamber of the plasma arc torch, The electrode for plasma arc torch, An electrode body made of an electrically conductive material and defining a longitudinal axis, the electrode body including a distal end and an adjacent end that receive a light emitting element; And An elastic element in physical contact with said adjacent end of said electrode body during said pilot arc operation to pass pilot arc current between said power supply and said electrode body during pilot arc operation of said plasma arc torch; Plasma arc torch electrode comprising a. The method of claim 1, The electrode body further comprising a reaction surface disposed in spaced relationship with respect to the adjacent end of the electrode body located spaced from a workpiece and configured to be in electrical communication with the resilient element of electrical conductivity. Electrode. The method of claim 2, And the reaction surface comprises a radially extending flange integrally formed with the electrode body. The method of claim 1, The elastic element is a plasma arc torch electrode, characterized in that fixed to the electrode body. The method of claim 4, wherein The elastic element is a plasma arc torch electrode, characterized in that fixed by the interference fit. The method of claim 1, The distal end of the electrode body includes the light emitting element. The method of claim 1, The elastic element is a plasma arc torch electrode, characterized in that formed integrally with the electrode body. The method of claim 1, Wherein said pilot arc operation comprises initiation of a pilot arc. The method of claim 1, And a hollow body for holding the elastic element and slidably accommodating the electrode body. The method of claim 9, And said hollow body is a vortex ring. An electrode for plasma arc torch in electrical communication with a power source, The electrode for the plasma arc torch is movable relative to the nozzle in the plasma chamber of the plasma arc torch, The electrode for plasma arc torch, An electrode body made of an electrically conductive material defining a distal end and a longitudinal axis comprising a light emitting element, said electrode body being movable relative to said plasma arc torch; And A first surface that facilitates electrical communication with the power source and a second surface that facilitates electrical communication with a corresponding contact surface of the electrode body when the plasma arc torch is operated in a transferred arc mode, A contact element disposed adjacent to an adjacent end of the electrode body, The second surface of the contact element is in physical contact with the contact surface of the electrode body during the transferred arc mode and there is no contact with the contact surface of the electrode body during initiation of a pilot arc. Arc torch electrode. delete The method of claim 11, wherein The electrode body further comprises a reaction surface in physical contact with a conductive elastic element, the reaction surface being disposed in a spaced relationship with the adjacent end of the electrode body and spaced apart from the distal end. Electrode. The method of claim 13, And the reaction surface is defined by a radially extending flange integrally formed with the electrode body. The method of claim 11, wherein And an electrically conductive elastic element in electrical communication with at least one of the contact element and the electrode body. The method of claim 15, The elastic element is a plasma arc torch electrode, characterized in that formed integrally with at least one of the electrode body and the contact element. The method of claim 15, The elastic element is a plasma arc torch electrode, characterized in that disposed adjacent to the adjacent end of the electrode body. The method of claim 15, The elastic element is a plasma arc torch electrode, characterized in that held by the electrode body. The method of claim 15, And said electrode body comprises a reaction surface integrally formed with said electrode body, said elastic element being disposed between said second surface and said reaction surface of said contact element. The method of claim 15, And the elastic element is configured to pass a pilot arc current between the power source and the electrode body during pilot arc operation. The method of claim 15, The elastic element is a plasma arc torch electrode, characterized in that it comprises at least one of a spring and a wire. The method of claim 11, wherein And at least a portion of the contact element is slidably coupled to the electrode body. The method of claim 22, And a portion of the contact element facilitates passage of a pilot arc current between the contact element and the electrode body when the contact element is slidably coupled with the electrode body. The method of claim 11, wherein The contact element is a plasma arc torch electrode, characterized in that held by the electrode body. The method of claim 11, wherein The contact element further comprises a connecting member defining an alignment surface to limit the radial movement of the electrode body. The method of claim 25, The connecting member is a plasma arc torch electrode, characterized in that formed integrally with the contact element. The method of claim 11, wherein The electrode body further comprises a receptor disposed adjacent to the adjacent end of the electrode body spaced apart from the workpiece, wherein the receptor is configured to prevent the contact element from being released from the electrode body Electrode for plasma arc torch. A contact element for passing a current between a power source and an electrode body slidably mounted in a torch body of a contact initiating plasma arc torch, A first surface that facilitates electrical communication with the power source; A second surface configured to be in electrical communication with a contact surface defined by an adjacent end of the electrode body; When the electrode body is in physical contact with the second surface, at least a portion of the transferred arc current passes through the contact element and passes between the power source and the electrode body for operation of the plasma arc torch in the transferred arc mode. Does ; And An electrically conductive elastic element disposed adjacent the electrode body to direct a pilot arc current to the electrode body from the power source during pilot arc operation of a plasma arc torch; Contact element comprising a. 29. The method of claim 28, And a connecting member extending from the second surface to slidably engage the electrode body. 30. The method of claim 29, And the connecting member is integrally formed with the second surface. 30. The method of claim 29, The connecting member further comprises a third surface configured to pass a portion of the transferred arc current between the power source and the electrode body when the plasma arc torch is operated in the transferred arc mode. device. 29. The method of claim 28, And a receiving portion surrounding a portion of an adjacent end of the electrode body. 33. The method of claim 32, The elastic element is a contact element, characterized in that disposed in the receiving portion. 29. The method of claim 28, At least one of said first surface and said second surface defines an annular surface. 29. The method of claim 28, And a third surface in electrical communication with the power source when the plasma arc torch is operated in the transferred arc mode and passing a portion of the arc current transferred between the power source and the electrode body. device. 29. The method of claim 28, And an alignment portion defining an axis, wherein the alignment portion is spaced apart from an adjacent end of the electrode body and is configured to limit radial movement of the electrode body. As an electrode for plasma arc torch, An electrode body made of an electrically conductive material and defining a longitudinal axis, The electrode body, A distal end defining a hole for receiving the light emitting element; An adjacent end defining a contact surface in electrical communication with the power source; And A first portion of the contact element comprises a receptor disposed within the adjacent end of the electrode body to receive at least a portion of the contact element so as to be physically spaced from the electrode body during initiation of a pilot arc, Wherein the first portion passes an arc current transferred between a power source and the electrode body when the plasma arc torch is operated in the transferred arc mode, wherein the aperture and the receptor are separated by the electrode body. Electrode for plasma arc torch. 39. The method of claim 37, At least a portion of the contact surface is disposed in the container. 39. The method of claim 38, The contact element is a plasma arc torch electrode, characterized in that it comprises an annular structure. 39. The method of claim 37, The receptor, Cylindrical portion; And And a confinement surface disposed at an adjacent end of the receptor to prevent the contact element from being released from the receptor in response to a portion of the contact element. 41. The method of claim 40, And the confinement surface comprises an annular structure. 41. The method of claim 40, The cylindrical portion is defined by a first diameter, the confinement surface comprises a second diameter, and the distal region of the connecting member of the contact element defines a third diameter, the third diameter being greater than the second diameter. A plasma arc torch electrode, characterized in that larger and smaller than the first diameter. 43. The method of claim 42, And the distal region is a distal end of the connecting member. 39. The method of claim 37, And the receptor further comprises a surface having a radial dimension formed along an axis of the receptor to limit radial movement of the electrode body. 45. The method of claim 44, And the radially dimensioned surface is in physical contact with a portion of the contact element received by the receptor. 39. The method of claim 37, The electrode body further comprises a reaction surface in contact with the conductive elastic element, the reaction surface is disposed in the spaced apart relationship with respect to the contact surface electrode for a plasma arc torch. The method of claim 46, And the reaction surface comprises a radially extending flange integrally formed with the electrode body. 39. The method of claim 37, And an electrically conductive elastic element fixed by the electrode body. 49. The method of claim 48 wherein The elastic element is a plasma arc torch electrode, characterized in that fixed by the interference fit. 49. The method of claim 48 wherein The elastic element is a plasma arc torch electrode, characterized in that disposed in the container. A contact element for allowing a current to flow between an electrode body and a power supply slidably mounted in a torch body of a contact initiating plasma arc torch, The electrode body includes a distal end including a light emitting element, The contact element, A first surface that facilitates electrical communication with the power source; And A second surface that facilitates electrical communication with an adjacent end of the electrode body, The second surface is not in contact with the adjacent end during initiation of a pilot arc and is transferred from the power source when the plasma arc torch is operated in the transferred arc mode by contacting the adjacent end during a transferred arc mode. At least a portion of the current passes between the first and second surfaces of the contact element to the electrode body. 52. The method of claim 51, And an electrically conductive elastic element disposed adjacent said electrode body for passing a pilot arc current between said power supply and said electrode body during pilot arc initiation. 52. The method of claim 51, And a connection member disposed between the second surface and the electrode body. 54. The method of claim 53, And the connecting member is integrally formed with the second surface. 54. The method of claim 53, And the connecting member defines an alignment surface and an axis spaced apart from the adjacent end to limit radial movement of the electrode body. 52. The method of claim 51, The first surface, the second surface, or the first surface and the second surface define an annular surface. 52. The method of claim 51, Apply radial movement with the gas flowing through the plasma arc torch, limit movement of the electrode body relative to the plasma arc torch, electrically insulate the electrode body from a nozzle of the plasma arc torch, and the gas causes the electrode to And a vortex ring portion for performing at least one of the functions of directing a plurality of pins on the body or any combination thereof. The method of claim 57, And the contact element is integrally formed with the vortex ring portion. Plasma arc torch, A power supply for providing current to the plasma arc torch; A plasma chamber defined by said electrode body and nozzle slidably mounted within said plasma arc torch along an axis defined by adjacent ends and distal ends of an electrically conductive electrode body; The proximal end defines a contact surface, the distal end disposed adjacent the outlet orifice of the nozzle; ; A power contact disposed in a fixed position relative to the plasma chamber and in electrical communication with the power source; An elastic conductive element for passing a pilot arc current between the contact surface of the electrode body and the power contact during pilot arc operation of the plasma arc torch; And A contact including a first surface in electrical communication with a corresponding contact surface of the electrode body and a second surface in physical contact with a power contact for passing an arc current transferred between the power source and the electrode body during a transferred arc mode. device; Plasma arc torch comprising a. The method of claim 59, And the elastic conductive element presses the electrode body toward the nozzle. The method of claim 59, And a second elastic element for pressing the electrode body toward the nozzle. The method of claim 59, And the contact element is disposed at a fixed position with respect to the electrode body. The method of claim 59, And the contact element is integrally formed with the power contact. The method of claim 59, And a shield defining an outlet port located adjacent the outlet orifice of the nozzle, the shield mounted on a fixed cap supported on the torch body of the plasma arc torch. The method of claim 59, And a vortex ring for exerting radial motion with respect to the gas flowing through said plasma arc torch. Plasma arc torch, A power supply for providing a current to the plasma arc torch; A plasma chamber defined by said electrode body and nozzle slidably mounted within said plasma arc torch along an axis defined by adjacent ends and distal ends of an electrically conductive electrode body; The electrode body defines a contact surface, the distal end being disposed adjacent the outlet orifice of the nozzle; ; A power contact disposed in a fixed position relative to the plasma chamber and in electrical communication with the power source; And An elastic conductive element for pressing the electrode body toward the nozzle by passing a pilot arc current between the contact surface of the electrode body and the power contact during pilot arc operation of the plasma arc torch; Plasma arc torch comprising a. The method of claim 66, wherein The power contact includes a first surface that facilitates physical contact and electrical communication with a corresponding second contact surface of the electrode body when the plasma arc torch is operated in a transferred arc mode; And said first surface is free of contact with said corresponding second contact surface of said electrode body during initiation of a pilot arc. An electrode for plasma arc torch in electrical communication with a power source, Consisting of an electrically conductive material, comprising an electrode body defining a longitudinal axis, The electrode body, A first surface in electrical communication with a first conductive element that facilitates passage of pilot arc current between the power source and the electrode body during initiation of a pilot arc; And A second surface located at a distance from the first surface, The second surface is in physical contact with and in electrical communication with a corresponding surface of a power contact to facilitate passage of the arc current transferred between the power source and the electrode body during a transferred arc operation, the second surface being the And no contact with the corresponding surface of the power contact during the start of the pilot arc. A hollow body of a plasma torch assembly that slidably receives an electrode at a second end, A first end and the second end; Internal surface; One or more contours, steps or flanges located on the inner surface and disposed between the first end and the second end of the hollow body, the opening of a shape adapted to slidably receive the complementary portion of the electrode One or more contours, steps, or flanges defining a ball; A first opening in said first end of said hollow body sized to receive an electrical contact element; And A second opening in said second end of said hollow body sized to slidably receive said electrode, The hollow body is configured to receive an electrically conductive elastic member at the first end to facilitate electrical conduction of a pilot arc, the elastic member being at least partially within the hollow body by the one or more contours, steps or flanges. And the elastic member is disposed in the hollow body so that the elastic member is aligned with the first opening. The method of claim 69, And a plurality of holes adjacent said second opening of said hollow body for applying a vortex flow to a gas. The method of claim 69, Wherein said electrical contact element is disposed within said first end of said hollow body, said electrical contact element retains said elastic member within said hollow body and facilitates electrical coupling between said elastic member and a power source. Hollow body of the plasma torch assembly.

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